ERC FUNDED PROJECTS

Parkinson’s disease (PD) is the second most common neurodegenerative disorder primarily caused by the progressive loss of dopaminergic (DA) neurons in the substantia nigra (SN). Despite the advances in gene discovery associated with PD, the knowledge of the PD pathogenesis is largely limited to the involvement of these genes in the generic cell death pathways, and why degeneration is specific to DA neurons and why the degeneration is progressive remain enigmatic. Broad goal of our work is therefore to elucidate the mechanisms underlying specific and progressive DA neuron degeneration in PD. Our new Drosophila model of PD ⎯Fer2 gene loss-of-function mutation⎯ is unusually well suited to address these questions. Fer2 mutants exhibit specific and progressive death of brain DA neurons as well as severe locomotor defects and short life span. Strikingly, the death of DA neuron is initiated in a small cluster of Fer2-expressing DA neurons and subsequently propagates to Fer2-negative DA neurons. We therefore propose a novel two-step model of the neurodegeneration in PD: primary cell death occurs in a specific subset of dopamindegic neurons that are genetically defined, and subsequently the failure of the neuronal connectivity triggers and propagates secondary cell death to remaining DA neurons. In this research, we will test this hypothesis and investigate the underlying molecular mechanisms. This will be the first study to examine circuit-dependency in DA neuron degeneration. Our approach will use a combination of non-biased genomic techniques and candidate-based screening, in addition to the powerful Drosophila genetic toolbox. Furthermore, to test this hypothesis beyond the Drosophila model, we will establish new mouse models of PD that exhibit progressive DA neuron degeneration. Outcome of this research will likely revolutionize the understanding of PD pathogenesis and open an avenue toward the discovery of effective therapy strategies against PD.

1 518 960 €

Start date: 2013-06-01, End date: 2018-05-31

The sub-cellular processes that control the most critical aspects of life occur in three-dimensions (3D), and are intrinsically dynamic. While super-resolution microscopy has revolutionized cellular imaging in recent years, our current capability to observe the dynamics of life on the nanoscale is still extremely limited, due to inherent trade-offs between spatial, temporal and spectral resolution using existing approaches. We propose to develop and demonstrate an optical microscopy methodology that would enable live sub-cellular observation in unprecedented detail. Making use of multicolor 3D point-spread-function (PSF) engineering, a technique I have recently developed, we will be able to simultaneously track multiple markers inside live cells, at high speed and in five-dimensions (3D, time, and color). Multicolor 3D PSF engineering holds the potential of being a uniquely powerful method for 5D tracking. However, it is not yet applicable to live-cell imaging, due to significant bottlenecks in optical engineering and signal processing, which we plan to overcome in this project. Importantly, we will also demonstrate the efficacy of our method using a challenging biological application: real-time visualization of chromatin dynamics - the spatiotemporal organization of DNA. This is a highly suitable problem due to its fundamental importance, its role in a variety of cellular processes, and the lack of appropriate tools for studying it. The project is divided into 3 aims: 1. Technology development: diffractive-element design for multicolor 3D PSFs. 2. System design: volumetric tracking of dense emitters. 3. Live-cell measurements: chromatin dynamics. Looking ahead, here we create the imaging tools that pave the way towards the holy grail of chromatin visualization: dynamic observation of the 3D positions of the ~3 billion DNA base-pairs in a live human cell. Beyond that, our results will be applicable to numerous 3D micro/nanoscale tracking applications.

1 802 500 €

Start date: 2018-11-01, End date: 2023-10-31

We propose to elucidate the structural design principles of naturally occurring antibody complementarity-determining regions (CDRs) and to computationally design novel antibody functions. Antibodies represent the most versatile known system for molecular recognition. Research has yielded many insights into antibody design principles and promising biotechnological and pharmaceutical applications. Still, our understanding of how CDRs encode specific loop conformations lags far behind our understanding of structure-function relationships in non-immunological scaffolds. Thus, design of antibodies from first principles has not been demonstrated. We propose a computational-experimental strategy to address this challenge. We will: (a) characterize the design principles and sequence elements that rigidify antibody CDRs. Natural antibody loops will be subjected to computational modeling, crystallography, and a combined in vitro evolution and deep-sequencing approach to isolate sequence features that rigidify loop backbones; (b) develop a novel computational-design strategy, which uses the >1000 solved structures of antibodies deposited in structure databases to realistically model CDRs and design them to recognize proteins that have not been co-crystallized with antibodies. For example, we will design novel antibodies targeting insulin, for which clinically useful diagnostics are needed. By accessing much larger sequence/structure spaces than are available to natural immune-system repertoires and experimental methods, computational antibody design could produce higher-specificity and higher-affinity binders, even to challenging targets; and (c) develop new strategies to program conformational change in CDRs, generating, e.g., the first allosteric antibodies. These will allow targeting, in principle, of any molecule, potentially revolutionizing how antibodies are generated for research and medicine, providing new insights on the design principles of protein functional sites.

1 499 930 €

Start date: 2013-09-01, End date: 2018-08-31

The centriole is the largest evolutionary conserved macromolecular structure responsible for building centrosomes and cilia or flagella in many eukaryotes. Centrioles are critical for the proper execution of important biological processes ranging from cell division to cell signaling. Moreover, centriolar defects have been associated to several human pathologies including ciliopathies and cancer. This state of facts emphasizes the importance of understanding centriole biogenesis. The study of centriole formation is a deep-rooted question, however our current knowledge on its molecular organization at high resolution remains fragmented and limited. In particular, exquisite details of the overall molecular architecture of the human centriole and in particular of its central core region are lacking to understand the basis of centriole organization and function. Resolving this important question represents a challenge that needs to be undertaken and will undoubtedly lead to groundbreaking advances. Another important question to tackle next is to develop innovative methods to enable the nanometric molecular mapping of centriolar proteins within distinct architectural elements of the centriole. This missing information will be key to unravel the molecular mechanisms behind centriolar organization. This research proposal aims at building a cartography of the human centriole by elucidating its molecular composition and architecture. To this end, we will combine the use of innovative and multidisciplinary techniques encompassing spatial proteomics, cryo-electron tomography, state-of-the-art microscopy and in vitro assays and to achieve a comprehensive molecular and structural view of the human centriole. All together, we expect that these advances will help understand basic principles underlying centriole and cilia formation as well as might have further relevance for human health.

1 498 965 €

Start date: 2017-01-01, End date: 2021-12-31

Our affective and motivational state is important for our decisions, actions and quality of life. Many pathological conditions affect this state. For example, addictive drugs are hyperactivating the reward system and trigger a strong motivation for continued drug intake, whereas many somatic and psychiatric diseases lead to an aversive state, characterized by loss of motivation. I will study specific neural circuits and mechanisms underlying reward and aversion, and how pathological signaling in these systems can trigger relapse in drug addiction. Given the important role of the dopaminergic neurons in the midbrain for many aspects of reward signaling, I will study how synaptic plasticity in these cells, and in their target neurons in the striatum, contribute to relapse in drug seeking. I will also study the circuits underlying aversion. Little is known about these circuits, but my hypothesis is that an important component of aversion is signaled by a specific neuronal population in the brainstem parabrachial nucleus, projecting to the central amygdala. We will test this hypothesis and also determine how this aversion circuit contributes to the persistence of addiction and to relapse. To dissect this complicated system, I am developing new genetic methods for manipulating and visualizing specific functional circuits in the mouse brain. My unique combination of state-of-the-art competence in transgenics and cutting edge knowledge in the anatomy and functional organization of the circuits behind reward and aversion should allow me to decode these systems, linking discrete circuits to behavior. Collectively, the results will indicate how signals encoding aversion and reward are integrated to control addictive behavior and they may identify novel avenues for treatment of drug addiction as well as aversion-related symptoms affecting patients with chronic inflammatory conditions and cancer.

1 500 000 €

Start date: 2010-10-01, End date: 2015-09-30

Obesity and its metabolic co-morbidities have given rise to a rapidly expanding ‘metabolic syndrome’ pandemic affecting hundreds of millions of individuals worldwide. The integrative genetic and environmental causes of the obesity pandemic remain elusive. White adipose tissue (WAT)-resident immune cells have recently been highlighted as important factors contributing to metabolic complications. However, a comprehensive understanding of the regulatory circuits governing their function and the cell type-specific mechanisms by which they contribute to the development of metabolic syndrome is lacking. Likewise, the gut microbiome has been suggested as a critical regulator of obesity, but the bacterial species and metabolites that influence WAT inflammation are entirely unknown. We propose to use our recently developed high-throughput genomic and gnotobiotic tools, integrated with CRISPR-mediated interrogation of gene function, microbial culturomics, and in-vivo metabolic analysis in newly generated mouse models, in order to achieve a new level of molecular understanding of how WAT immune cells integrate environmental cues into their crosstalk with organismal metabolism, and to explore the microbial contributions to the molecular etiology of WAT inflammation in the pathogenesis of diet-induced obesity. Specifically, we aim to (a) decipher the global regulatory landscape and interaction networks of WAT hematopoietic cells at the single-cell level, (b) identify new mediators of WAT immune cell contributions to metabolic homeostasis, and (c) decode how host-microbiome communication shapes the development of WAT inflammation and obesity. Unraveling the principles of WAT immune cell regulation and their amenability to change by host-microbiota interactions may lead to a conceptual leap forward in our understanding of metabolic physiology and disease. Concomitantly, it may generate a platform for microbiome-based personalized therapy against obesity and its complications.

2 000 000 €

Start date: 2019-03-01, End date: 2024-02-29

Our tissues are constantly renewed by stem cells. Over time, stem cells accumulate cellular damage that will compromise renewal and results in aging. As stem cells can divide asymmetrically, segregation of harmful factors to the differentiating daughter cell could be one possible mechanism for slowing damage accumulation in the stem cell. However, current evidence for such mechanisms comes mainly from analogous findings in yeast, and studies have concentrated only on few types of cellular damage. I hypothesize that the chronological age of a subcellular component is a proxy for all the damage it has sustained. In order to secure regeneration, mammalian stem cells may therefore specifically sort old cellular material asymmetrically. To study this, I have developed a novel strategy and tools to address the age-selective segregation of any protein in stem cell division. Using this approach, I have already discovered that stem-like cells of the human mammary epithelium indeed apportion chronologically old mitochondria asymmetrically in cell division, and enrich old mitochondria to the differentiating daughter cell. We will investigate the mechanisms underlying this novel phenomenon, and its relevance for mammalian aging. We will first identify how old and young mitochondria differ, and how stem cells recognize them to facilitate the asymmetric segregation. Next, we will analyze the extent of asymmetric age-selective segregation by targeting several other subcellular compartments in a stem cell division. Finally, we will determine whether the discovered age-selective segregation is a general property of stem cell in vivo, and it's functional relevance for maintenance of stem cells and tissue regeneration. Our discoveries may open new possibilities to target aging associated functional decline by induction of asymmetric age-selective organelle segregation.

1 500 000 €

Start date: 2016-05-01, End date: 2021-04-30

Drones are disrupting industries, such as agriculture, package delivery, inspection, and search and rescue. However, they are still either controlled by a human pilot or heavily rely on GPS for navigating autonomously. The alternative to GPS are onboard sensors, such as cameras: from the raw data, a local 3D map of the environment is built, which is then used to plan a safe trajectory to the goal. While the underlying algorithms are well understood, we are still far from having autonomous drones that can navigate through complex environments as good as human pilots. State-of-the-art perception and control algorithms are mature but not robust: coping with unreliable state estimation, low-latency perception, real-time planning in dynamic environments, and tight coupling of perception and action under severe resource constraints are all still unsolved research problems. Another issue is that, because battery energy density is increasing at a very slow rate, drones need to navigate faster in order to accomplish more within their limited flight time. To obtain more agile robots, we need faster sensors and low-latency processing. The goal of this project is to develop novel scientific methods that would allow me to demonstrate autonomous, vision-based, agile quadrotor navigation in unknown, GPS-denied, and cluttered environments with possibly moving obstacles, which can be as effective in terms of maneuverability and agility as those of professional drone pilots. The outcome would not only be beneficial for disaster response scenarios, but also for other scenarios, such as aerial delivery or inspection. To achieve this ambitious goal, I will first develop robust, low-latency, multimodal perception algorithms that combine the advantages of standard cameras with event cameras. Then, I will develop novel methods that unify perception and state estimation together with planning and control to enable agile maneuvers through cluttered, unknown, and dynamic environments.

2 000 000 €

Start date: 2020-09-01, End date: 2025-08-31

The Type 6 secretion system (T6SS) allows Gram-negative bacteria to deliver toxins into both eukaryotic and bacterial target cells and thus cause disease or kill competitors. T6SS is composed of four main parts: a membrane complex, a baseplate and a long spring-like sheath wrapped around an inner tube. Sheath contraction generates a large amount of energy to push the tube with associated toxins through the baseplate and membrane complex out of the cell. However, the reach of the T6SS tube is limited and thus a direct contact with the target membrane and precise positioning of T6SS assembly is required for protein translocation. In this proposal, we will unravel principles of spatial and temporal coordination of T6SS assembly that we have recently observed in several bacterial species. We will study how cells sense attacks from neighboring bacteria to dynamically localize its T6SS. We will describe how bacteria initiate and position T6SS assembly in response to physical cell-cell interactions. We will identify the principles and the role of T6SS localization in intracellular pathogens. Using genetic and biochemical approaches, we will identify and characterize proteins interacting with the core components of T6SS and test their role in initiation and positioning of T6SS assembly. We will search for peptidoglycan remodeling enzymes required for T6SS assembly. We will use advanced microscopy techniques to describe dynamic localization of proteins upon T6SS activation to establish the order of their assembly. We will quantify how much T6SS aiming increases efficiency of protein delivery and T6SS function during bacterial competition and pathogenesis. Overall, we will unravel novel principles of spatial and temporal control of localization of protein complexes and show how this allows bacteria to quickly respond to external cues and interact with their environment.

2 493 650 €

Start date: 2021-01-01, End date: 2025-12-31

Real-world optimization problems pose major challenges to algorithmic research. For instance, (i) many important problems are believed to be intractable (i.e. NP-hard) and (ii) with the growth of data size, modern applications often require a decision making under {\em incomplete and dynamically changing input data}. After several decades of research, central problems in these domains have remained poorly understood (e.g. Is there an asymptotically most efficient binary search trees?) Existing algorithmic techniques either reach their limitation or are inherently tailored to special cases. This project attempts to untangle this gap in the state of the art and seeks new interplay across multiple areas of algorithms, such as approximation algorithms, online algorithms, fixed-parameter tractable (FPT) algorithms, exponential time algorithms, and data structures. We propose new directions from the {\em structural perspectives} that connect the aforementioned algorithmic problems to basic questions in combinatorics. Our approaches fall into one of the three broad schemes: (i) new structural theory, (ii) intermediate problems, and (iii) transfer of techniques. These directions partially build on the PI's successes in resolving more than ten classical problems in this context. Resolving the proposed problems will likely revolutionize our understanding about algorithms and data structures and potentially unify techniques in multiple algorithmic regimes. Any progress is, in fact, already a significant contribution to the algorithms community. We suggest concrete intermediate goals that are of independent interest and have lower risks, so they are suitable for Ph.D students.

1 411 258 €

Start date: 2018-02-01, End date: 2023-01-31

Recurrent neural networks (RNNs) are general parallel-sequential computers. Some learn their programs or weights. Our supervised Long Short-Term Memory (LSTM) RNNs were the first to win pattern recognition contests, and recently enabled best known results in speech and handwriting recognition, machine translation, etc. They are now available to billions of users through the world's most valuable public companies including Google and Apple. Nevertheless, in lots of real-world tasks RNNs do not yet live up to their full potential. Although universal in theory, in practice they fail to learn important types of algorithms. This ERC project will go far beyond today's best RNNs through novel RNN-like systems that address some of the biggest open RNN problems and hottest RNN research topics: (1) How can RNNs learn to control (through internal spotlights of attention) separate large short-memory structures such as sub-networks with fast weights, to improve performance on many natural short-term memory-intensive tasks which are currently hard to learn by RNNs, such as answering detailed questions on recently observed videos? (2) How can such RNN-like systems metalearn entire learning algorithms that outperform the original learning algorithms? (3) How to achieve efficient transfer learning from one RNN-learned set of problem-solving programs to new RNN programs solving new tasks? In other words, how can one RNN-like system actively learn to exploit algorithmic information contained in the programs running on another? We will test our systems existing benchmarks, and create new, more challenging multi-task benchmarks. This will be supported by a rather cheap, GPU-based mini-brain for implementing large RNNs.

2 500 000 €

Start date: 2017-10-01, End date: 2022-09-30

As diploid organisms inherit one gene copy from each parent, a gene can be expressed from both alleles (biallelic) or from only one allele (monoallelic). Although transcription from both alleles is detected for most genes in cell population experiments, little is known about allele-specific expression in single cells and its phenotypic consequences. To answer fundamental questions about allelic transcription heterogeneity in single cells, this research program will focus on single-cell transcriptome analyses with allelic-origin resolution. To this end, we will investigate both clonally stable and dynamic random monoallelic expression across a large number of cell types, including cells from embryonic and adult stages. This research program will be accomplished with the novel single-cell RNA-seq method developed within my lab to obtain quantitative, genome-wide gene expression measurement. To distinguish between mitotically stable and dynamic patterns of allelic expression, we will analyze large numbers a clonally related cells per cell type, from both primary cultures (in vitro) and using transgenic models to obtain clonally related cells in vivo. The biological significance of the research program is first an understanding of allelic transcription, including the nature and extent of random monoallelic expression across in vivo tissues and cell types. These novel insights into allelic transcription will be important for an improved understanding of how variable phenotypes (e.g. incomplete penetrance and variable expressivity) can arise in genetically identical individuals. Additionally, the single-cell transcriptome analyses of clonally related cells in vivo will provide unique insights into the clonality of gene expression per se.

1 923 060 €

Start date: 2015-07-01, End date: 2020-12-31

This proposal targets the emerging frontier research field of multiple-input multiple-output (MIMO) systems along with several innovative and somewhat unconventional applications of such systems. The use of arrays of transmitters and receivers will have a profound impact on future medical imaging/therapy systems, radar systems, and radio communication networks. Multiple transmitters provide a tremendous versatility and allow waveforms to be adapted temporally and spatially to environmental conditions. This is useful for individually tailored illumination of human tissue in biomedical imaging or ultrasound therapy. In radar systems, multiple transmit beams can be formed simultaneously via separate waveform designs allowing accurate target classification. In a wireless communication system, multiple communication signals can be directed to one or more users at the same time on the same frequency carrier. In addition, multiple receivers can be used in the above applications to provide increased detection performance, interference rejection, and improved estimation accuracy. The joint modelling, analysis, and design of these multidimensional transmit and receive schemes form the core of this research proposal. Ultimately, our research aims at developing the fundamental tools that will allow the design of wireless communication systems with an order-of-magnitude higher capacity at a lower cost than today; of ultrasound therapy systems maximizing delivered power while reducing treatment duration and unwanted illumination; and of distributed aperture multi-beam radars allowing more effective target location, identification, and classification. Europe has several successful industries that are active in biomedical imaging/therapy, radar systems, and wireless communications. The future success of these sectors critically depends on the ability to innovate and integrate new technology.

1 872 720 €

Start date: 2009-01-01, End date: 2013-12-31

This proposal outlines a highly ambitious and path-breaking research program. Through a tightly integrated package of basic theoretical work, strategic empirical research projects, international workshops, and a large number of publications in leading journals, the research program seeks to move sociology in a more analytical direction. One part of the research program focuses on the epistemological and methodological foundations of analytical sociology, an approach to sociological theory and research that currently receives considerable attention in the international scholarly community. This work will be organized around two core themes: (1) the principles of mechanism-based explanations and (2) the micro-macro link. The empirical research analyzes in great detail the ethnic, gender, and socio-economic segregation of key interaction domains in Sweden using the approach of analytical sociology. The interaction domains focused upon are schools, workplaces and neighborhoods; domains where people spend a considerable part of their time, where much of the social interaction between people takes place, where identities are formed, and where important resources are distributed. Large-scale longitudinal micro data on the entire Swedish population, unique longitudinal data on social networks within school classes, and various agent-based simulation techniques, are used to better understand the processes through which schools, workplaces and neighborhoods become segregated along various dimensions, how the domains interact with one another, and how the structure and extent of segregation affects diverse social and economic outcomes.

1 745 098 €

Start date: 2013-03-01, End date: 2018-02-28

Calcium-activated chloride channels (CaCCs) play key roles in a range of physiological processes such as the control of membrane excitability, photoreception and epithelial secretion. Although the importance of these channels has been recognized for more than 30 years their molecular identity remained obscure. The recent discovery of two protein families encoding for CaCCs, Anoctamins and Bestrophins, was a scientific breakthrough that has provided first insight into two novel ion channel architectures. Within this proposal we aim to determine the first high resolution structures of members of both families and study their functional behavior by an interdisciplinary approach combining biochemistry, X-ray crystallography and electrophysiology. The structural investigation of eukaryotic membrane proteins is extremely challenging and will require us to investigate large numbers of candidates to single out family members with superior biochemical properties. During the last year we have made large progress in this direction. By screening numerous eukaryotic Anoctamins and prokaryotic Bestrophins we have identified well-behaved proteins for both families, which were successfully scaled-up and purified. Additional family members will be identified within the course of the project. For these stable proteins we plan to grow crystals diffracting to high resolution and to proceed with structure determination. With first structural information in hand we will perform detailed functional studies using electrophysiology and complementary biophysical techniques to gain mechanistic insight into ion permeation and gating. As the pharmacology of both families is still in its infancy we will in later stages also engage in the identification and characterization of inhibitors and activators of Anoctamins and Bestrophins to open up a field that may ultimately lead to the discovery of novel therapeutic strategies targeting calcium-activated chloride channels.

2 176 000 €

Start date: 2014-02-01, End date: 2020-01-31

Dysregulation of capillary permeability is a severe problem in critically ill patients, but the mechanisms involved are poorly understood. Further, there are no targeted therapies to stabilize leaky vessels in various common, potentially fatal diseases, such as systemic inflammation and sepsis, which affect millions of people annually. Although a multitude of signals that stimulate opening of endothelial cell-cell junctions leading to permeability have been characterized using cellular and in vivo models, approaches to reverse the harmful process of capillary leakage in disease conditions are yet to be identified. I propose to explore a novel autocrine endothelial permeability regulatory system as a potentially universal mechanism that antagonizes vascular stabilizing ques and sustains vascular leakage in inflammation. My group has identified inflammation-induced mechanisms that switch vascular stabilizing factors into molecules that destabilize vascular barriers, and identified tools to prevent the barrier disruption. Building on these discoveries, my group will use mouse genetics, structural biology and innovative, systematic antibody development coupled with gene editing and gene silencing technology, in order to elucidate mechanisms of vascular barrier breakdown and repair in systemic inflammation. The expected outcomes include insights into endothelial cell signaling and permeability regulation, and preclinical proof-of-concept antibodies to control endothelial activation and vascular leakage in systemic inflammation and sepsis models. Ultimately, the new knowledge and preclinical tools developed in this project may facilitate future development of targeted approaches against vascular leakage.

1 999 770 €

Start date: 2018-05-01, End date: 2023-04-30

"Recent technological evolutions, including the cloud, the multicore, the social and the mobiles ones, are turning computing ubiquitously distributed. Yet, building high-assurance distributed programs is notoriously challenging. One of the main reasons is that these systems usually seek to achieve several goals at the same time. In short, they need to be efficient, responding effectively in various average-case conditions, as well as reliable, behaving correctly in severe, worst-case conditions. As a consequence, they typically intermingle different strategies: each to cope with some specific condition, e.g., with or without node failures, message losses, time-outs, contention, cache misses, over-sizing, malicious attacks, etc. The resulting programs end up hard to design, prove, verify, implement, test and debug. Not surprisingly, there are anecdotal evidences of the fragility of the most celebrated distributed systems. The goal of this project is to contribute to building high-assurance distributed programs by introducing a new dimension for separating and isolating their concerns, as well as a new scheme for composing and reusing them in a modular manner. In short, the project will explore the inherent power and limitations of a novel paradigm, Adversary-Oriented Computing (AOC). Sub-programs, each implementing a specific strategy to cope with a given adversary, modelling a specific working condition, are designed, proved, verified, implemented, tested and debugged independently. They are then composed, possibly dynamically, as black-boxes within the same global program. The AOC project is ambitious and it seeks to fundamentally revisit the way distributed algorithms are designed and distributed systems are implemented. The gain expected in comparison with today's approaches is substantial, and I believe it will be proportional to the degree of difficulty of the distributed problem at hand."

2 147 012 €

Start date: 2014-06-01, End date: 2019-05-31

Novel sophisticated technologies that exploit the laws of quantum physics form a cornerstone for the future well-being, economic growth and security of Europe. Here photonic devices have gained a prominent position because the absorption, emission, propagation or storage of a photon is a process that can be harnessed at a fundamental level and render more practical ways to use light for such applications. However, the interaction of light with single quantum systems under ambient conditions is typically very weak and difficult to control. Furthermore, there are quantum phenomena occurring in matter at nanometer length scales that are currently not well understood. These deficiencies have a direct and severe impact on creating a bridge between quantum physics and photonic device technologies. aQUARiUM, precisely address the issue of controlling and enhancing the interaction between few photons and rolled-up nanostructures with ability to be deployed in practical applications. With aQUARiUM, we will take epsilon (permittivity)-near-zero (ENZ) metamaterials into quantum nanophotonics. To this end, we will integrate quantum emitters with rolled-up waveguides, that act as ENZ metamaterial, to expand and redefine the range of light-matter interactions. We will explore the electromagnetic design freedom enabled by the extended modes of ENZ medium, which “stretches” the effective wavelength inside the structure. Specifically, aQUARiUM is built around the following two objectives: (i) Enhancing light-matter interactions with single emitters (Enhance) independent of emitter position. (ii) Enabling collective excitations in dense emitter ensembles (Collect) coherently connect emitters on nanophotonic devices to obtain coherent emission. aQUARiUM aims to create novel light-sources and long-term entanglement generation and beyond. The envisioned outcome of aQUARiUM is a wholly new photonic platform applicable across a diverse range of areas.

1 499 431 €

Start date: 2019-01-01, End date: 2023-12-31

Axon growth potential declines during development, contributing to the lack of effective regeneration in the adult central nervous system. What determines the intrinsic growth potential of neurites, and how such growth is regulated during development, disease and following injury is a fundamental question in neuroscience. Although multiple lines of evidence indicate that intrinsic growth capability is genetically encoded, its nature remains poorly defined. Neuronal remodeling of the Drosophila mushroom body offers a unique opportunity to study the mechanisms of various types of axon degeneration and growth. We have recently demonstrated that regrowth of axons following developmental pruning is not only distinct from initial outgrowth but also shares molecular similarities with regeneration following injury. In this proposal we combine state of the art tools from genomics, functional genetics and microscopy to perform a comprehensive study of the mechanisms underlying axon growth during development and following injury. First, we will combine genetic, biochemical and genomic studies to gain a mechanistic understanding of the developmental regrowth program. Next, we will perform extensive transcriptomic analyses and comparisons aimed at defining the genetic programs involved in initial axon growth, developmental regrowth, and regeneration following injury. Finally, we will harness the genetic power of Drosophila to perform a comprehensive functional analysis of genes and pathways, those previously known and new ones that we will discover, in various neurite growth paradigms. Importantly, these functional assays will be performed in the same organism, allowing us to use identical genetic mutations across our analyses. To this end, our identification of a new genetic program regulating developmental axon regrowth, together with emerging tools in genomics, places us in a unique position to gain a broad understanding of axon growth during development and following injury.

2 000 000 €

Start date: 2014-03-01, End date: 2019-02-28

This proposal aims at understanding how B cell specificity and immunodominance shape primary and secondary humoral responses to influenza A virus. Influenza A virus is a relevant human pathogen causing a considerable yearly death toll and economic burden to society. Immunodominance is a major driving force of adaptive immunity and defines the hierarchical recognition of epitopes on the same antigen. Previous studies analysing B cell dynamics in primary and secondary responses have been mainly focusing on simple antigens and competition between B cell clones of the same family. Investigation using complex antigens and examining interclonal competition are surprisingly scarce. Influenza hemagglutinin (HA) is a prime candidate to study immunodominance in B cells. I have generated a set of mutant viruses that will allow for an unprecedented investigation into immunodominance and B cell interclonal competition in primary and secondary responses. These viruses can be used to isolate and enumerate antibody and B cells specific for different epitopes on the same complex antigen (HA). I will use these unique tools in combination with state-of-the-art immunological methods, multi-colour flow cytometry and single cells RNA sequencing paired with B cell receptor sequencing to gain fundamental insights into B cell regulation and anti-viral humoral responses. I will i) study the link between B cell receptor characteristics, specificity and B cell fate decisions in primary responses, ii) characterize the relative contribution of pre-existing B cells, serum antibodies and CD4 T cells for immunodominance of secondary responses, iii) define immunodominance in human individuals, repeatedly exposed to influenza virus. I expect this project to critically improve our understanding of basic B cell biology with the long-term benefit of improving current vaccination against variable viral pathogens.

1 481 697 €

Start date: 2019-12-01, End date: 2024-11-30

Bacteria in nature exhibit remarkable capacity to sense their surroundings and rapidly adapt to diverse conditions by gaining new beneficial traits. This extraordinary feature facilitates their survival when facing extreme environments. Utilizing Bacillus subtilis as our primary model organism, we propose to study two facets of this vital bacterial attribute: communication via extracellular nanotubes, and persistence as resilient spores while maintaining the potential to revive. Exploring these fascinating aspects of bacterial physiology is likely to change our view as to how bacteria sense, respond, endure and communicate with their extracellular environment. We have recently discovered a previously uncharacterized mode of bacterial communication, mediated by tubular extensions (nanotubes) that bridge neighboring cells, providing a route for exchange of intracellular molecules. Nanotube-mediated molecular sharing may represent a key form of bacterial communication in nature, allowing for the emergence of new phenotypes and increasing survival in fluctuating environments. Here we propose to develop strategies for observing nanotube formation and molecular exchange in living bacterial cells, and to characterize the molecular composition of nanotubes. We will explore the premise that nanotubes serve as a strategy to expand the cell surface, and will determine whether nanotubes provide a conduit for phage infection and spreading. Furthermore, the formation and functionality of interspecies nanotubes will be explored. An additional mode employed by bacteria to achieve extreme robustness is the ability to reside as long lasting spores. Previously held views considered the spore to be dormant and metabolically inert. However, we have recently shown that at least one week following spore formation, during an adaptive period, the spore senses and responds to environmental cues and undergoes corresponding molecular changes, influencing subsequent emergence from quiescence.

1 497 800 €

Start date: 2014-04-01, End date: 2019-03-31

Distributed systems underlie many modern technologies, a prime example being the Internet. The ever-increasing abundance of distributed systems necessitates their design and usage to be backed by strong theoretical foundations. A major challenge that distributed systems face is the lack of a central authority, which brings many aspects of uncertainty into the environment, in the form of unknown network topology or unpredictable dynamic behavior. A practical restriction of distributed systems, which is at the heart of this proposal, is the limited bandwidth available for communication between the network components. A central family of distributed tasks is that of local tasks, which are informally described as tasks which are possible to solve by sending information through only a relatively small number of hops. A cornerstone example is the need to break symmetry and provide a better utilization of resources, which can be obtained by the task of producing a valid coloring of the nodes given some small number of colors. Amazingly, there are still huge gaps between the known upper and lower bounds for the complexity of many local tasks. This holds even if one allows powerful assumptions of unlimited bandwidth. While some known algorithms indeed use small messages, the complexity gaps are even larger compared to the unlimited bandwidth case. This is not a mere coincidence, and in fact the existing theoretical infrastructure is provably incapable of giving stronger lower bounds for many local tasks under limited bandwidth. This proposal zooms in on this crucial blind spot in the current literature on the theory of distributed computing, namely, the study of local tasks under limited bandwidth. The goal of this research is to produce fast algorithms for fundamental distributed local tasks under restricted bandwidth, as well as understand their limitations by providing lower bounds.

1 486 480 €

Start date: 2018-06-01, End date: 2023-05-31

Asymmetric cell division is a key mechanism for the generation of cell diversity in eukaryotes. During this process, a polarized mother cell divides into non-equivalent daughters. These may differentially inherit fate determinants, irreparable damages or age determinants. Our aim is to decipher the mechanisms governing the individualization of daughters from each other. In the past ten years, our studies identified several lateral diffusion barriers located in the plasma membrane and the endoplasmic reticulum of budding yeast. These barriers all restrict molecular exchanges between the mother cell and its bud, and thereby compartmentalize the cell already long before its division. They play key roles in the asymmetric segregation of various factors. On one side, they help maintain polarized factors into the bud. Thereby, they reinforce cell polarity and sequester daughter-specific fate determinants into the bud. On the other side they prevent aging factors of the mother from entering the bud. Hence, they play key roles in the rejuvenation of the bud, in the aging of the mother, and in the differentiation of mother and daughter from each other. Recently, we accumulated evidence that some of these barriers are subject to regulation, such as to help modulate the longevity of the mother cell in response to environmental signals. Our data also suggest that barriers help the mother cell keep traces of its life history, thereby contributing to its individuation and adaption to the environment. In this project, we will address the following questions: 1 How are these barriers assembled, functioning, and regulated? 2 What type of differentiation processes are they involved in? 3 Are they conserved in other eukaryotes, and what are their functions outside of budding yeast? These studies will shed light into the principles underlying and linking aging, rejuvenation and differentiation.

2 200 000 €

Start date: 2010-05-01, End date: 2015-04-30

In the bone-enclosed CNS, increased vascular permeability may cause life-threatening tissue swelling, and/or ischemia and inflammation which compromise tissue repair after trauma or stroke. The brain vasculature possesses several unique features collectively named the blood-brain barrier (BBB) in which passive permeability is almost completely abolished and replaced by a complex of specific transport mechanisms. The BBB is necessary to uphold the specific milieu necessary for neuronal function. Whereas breakdown of the BBB is part of many CNS diseases, including stroke, neuroinflammation, trauma and neurodegenerative disorders, its molecular mechanisms and consequences are unclear and debated. Conversely, the intact BBB is a huge obstacle for drug delivery to the brain. Research on the BBB therefore has two seemingly opposing aims: 1) to seal a damaged BBB and protect the brain from toxic blood products, and 2) to open the BBB “on demand” for drug delivery. A major problem in the BBB field has been the lack of in vivo animal models for molecular and functional studies. So far, available in vitro models are not recapitulating the in vivo BBB. Our recent work on mouse models lacking pericytes, a BBB-associated cell type, demonstrates a specific role for pericytes in the development and regulation of the mammalian BBB. These animal models are the first ones showing a general and significant BBB impairment in adulthood, and as such they provide a unique opportunity to address molecular mechanisms of BBB disruption in disease and in drug transport across the BBB. Importantly, the new models and tools that we have developed allow us to search for relevant druggable mechanisms and molecular targets in the BBB. The long-term goals of this proposal are to develop molecular strategies and tools to open and close the BBB “on demand” for drug delivery to the CNS, and to explore the importance and mechanisms of BBB dysfunction in neurodegenerative diseases and stroke.

2 499 427 €

Start date: 2012-08-01, End date: 2017-07-31

A fundamental question in biology is why different individuals show different behaviors. While individuality in behavior is usually explained by genetic heterogeneity or differences in environmental exposures, more recent studies have shown that stable behavioral variation is also observed among isogenic individuals that were raised in the same environment. However, this important and potentially conserved epigenetic source of individual-to-individual behavioral variation remains largely unexplored. I have recently developed a novel imaging setup, using C. elegans, that allowed for the first time to study behavioral individuality across the full development time of animals, at high spatiotemporal resolution and under tightly controlled environmental conditions (Stern et al. Cell 2017). By using this unique system I found that isogenic animals show long-term behavioral individuality that persists across all developmental stages, and was dependent on specific neuromodulators. In this proposal I suggest to study how behavioral individuality emerges across development from non-genetic differences among individuals. In particular, I plan to (i) identify neuronal circuits and variations therein that lead to different behavioral states among individuals by combining my established methods for longitudinal behavioral quantifications with cutting-edge neuronal imaging and molecular techniques; (ii) study the role of conserved epigenetic mechanisms in generating stable neuronal and behavioral variations by integrating high-throughput gene-expression, neuronal, and behavioral analyses in single animals; and (iii) explore how stressful conditions affect behavioral individuality. I hypothesize that stress may enhance variation as a population-level mechanism to diversify risk in the face of complex or unpredictable conditions. The proposed research will shed light on novel processes that establish and maintain inter-individual diversity in neuronal and behavioral patterns.

1 375 000 €

Start date: 2019-12-01, End date: 2024-11-30

A fundamental challenge of pancreas biology is to understand and manipulate the determinants of beta cell mass. The homeostatic maintenance of adult beta cell mass relies largely on replication of differentiated beta cells, but the triggers and signaling pathways involved remain poorly understood. Here I propose to investigate the physiological and molecular mechanisms that control beta cell replication. First, novel transgenic mouse tools will be used to isolate live replicating beta cells and to examine the genetic program of beta cell replication in vivo. Information gained will provide insights into the molecular biology of cell division in vivo. Additionally, these experiments will address critical unresolved questions in beta cell biology, for example whether duplication involves transient dedifferentiation. Second, genetic and pharmacologic tools will be used to dissect the signaling pathways controlling the entry of beta cells to the cell division cycle, with emphasis on the roles of glucose and insulin, the key physiological input and output of beta cells. The expected outcome of these studies is a detailed molecular understanding of the homeostatic maintenance of beta cell mass, describing how beta cell function is linked to beta cell number in vivo. This may suggest new targets and concepts for pharmacologic intervention, towards the development of regenerative therapy strategies in diabetes. More generally, the experiments will shed light on one of the greatest mysteries of developmental biology, namely how organs achieve and maintain their correct size. A fundamental challenge of pancreas biology is to understand and manipulate the determinants of beta cell mass. The homeostatic maintenance of adult beta cell mass relies largely on replication of differentiated beta cells, but the triggers and signaling pathways involved remain poorly understood. Here I propose to investigate the physiological and molecular mechanisms that control beta cell replication. First, novel transgenic mouse tools will be used to isolate live replicating beta cells and to examine the genetic program of beta cell replication in vivo. Information gained will provide insights into the molecular biology of cell division in vivo. Additionally, these experiments will address critical unresolved questions in beta cell biology, for example whether duplication involves transient dedifferentiation. Second, genetic and pharmacologic tools will be used to dissect the signaling pathways controlling the entry of beta cells to the cell division cycle, with emphasis on the roles of glucose and insulin, the key physiological input and output of beta cells. The expected outcome of these studies is a detailed molecular understanding of the homeostatic maintenance of beta cell mass, describing how beta cell function is linked to beta cell number in vivo. This may suggest new targets and concepts for pharmacologic intervention, towards the development of regenerative therapy strategies in diabetes. More generally, the experiments will shed light on one of the greatest mysteries of developmental biology, namely how organs achieve and maintain their correct size.

1 445 000 €

Start date: 2010-09-01, End date: 2015-08-31

The goal of this proposal is to fundamentally change the way we build and reason about software. We aim to develop new kinds of statistical programming systems that provide probabilistically likely solutions to tasks that are difficult or impossible to solve with traditional approaches. These statistical programming systems will be based on probabilistic models of massive codebases (also known as ``Big Code'') built via a combination of advanced programming languages and powerful machine learning and natural language processing techniques. To solve a particular challenge, a statistical programming system will query a probabilistic model, compute the most likely predictions, and present those to the developer. Based on probabilistic models of ``Big Code'', we propose to investigate new statistical techniques in the context of three fundamental research directions: i) statistical program synthesis where we develop techniques that automatically synthesize and predict new programs, ii) statistical prediction of program properties where we develop new techniques that can predict important facts (e.g., types) about programs, and iii) statistical translation of programs where we investigate new techniques for statistical translation of programs (e.g., from one programming language to another, or to a natural language). We believe the research direction outlined in this interdisciplinary proposal opens a new and exciting area of computer science. This area will combine sophisticated statistical learning and advanced programming language techniques for building the next-generation statistical programming systems. We expect the results of this proposal to have an immediate impact upon millions of developers worldwide, triggering a paradigm shift in the way tomorrow's software is built, as well as a long-lasting impact on scientific fields such as machine learning, natural language processing, programming languages and software engineering.

1 500 000 €

Start date: 2016-04-01, End date: 2021-03-31

Identifying risk factors for diseases that can be prevented or delayed by early intervention is of major importance, and numerous genetic, lifestyle, anthropometric and clinical risk factors were found for many different diseases. Another source of potentially pertinent disease risk factors is the human microbiome - the collective genome of trillions of bacteria, viruses, fungi, and parasites that reside in the human gut. However, very few microbiome disease markers were found to date. Here, we aim to develop risk prediction tools based on the human microbiome that predict the likelihood of an individual to develop a particular condition or disease within 5-10 years. We will use a cohort of >2200 individuals that my group previously assembled, for whom we have clinical profiles, gut microbiome data, and banked blood and stool samples. We will invite people 5-10 years after their initial recruitment time, profile disease status and blood markers, and develop algorithms for predicting 5-10 year onset of Type 2 diabetes, cardiovascular disease, and obesity, using microbiome data from recruitment time. To increase the likelihood of finding microbiome markers predictive of disease onset, we will develop novel experimental and computational methods for in-depth characterization of microbial gene function, the metabolites produced by the microbiome, the underexplored fungal microbiome members, and the interactions between the gut microbiota and the host adaptive immune system. We will then apply these methods to >2200 banked samples from cohort recruitment time and use the resulting data in devising our microbiome-based risk prediction tools. In themselves, these novel assays and their application to >2200 samples should greatly advance the microbiome field. If successful, our proposal will identify new disease risk factors and risk prediction tools based on the microbiome, paving the way towards using the microbiome in early disease detection and prevention.

2 500 000 €

Start date: 2019-03-01, End date: 2024-02-29

All day long, our fingers touch, grasp and move objects in various media such as air, water, oil. We do this almost effortlessly - it feels like we do not spend time planning and reflecting over what our hands and fingers do or how the continuous integration of various sensory modalities such as vision, touch, proprioception, hearing help us to outperform any other biological system in the variety of the interaction tasks that we can execute. Largely overlooked, and perhaps most fascinating is the ease with which we perform these interactions resulting in a belief that these are also easy to accomplish in artificial systems such as robots. However, there are still no robots that can easily hand-wash dishes, button a shirt or peel a potato. Our claim is that this is fundamentally a problem of appropriate representation or parameterization. When interacting with objects, the robot needs to consider geometric, topological, and physical properties of objects. This can be done either explicitly, by modeling and representing these properties, or implicitly, by learning them from data. The main scientific objective of this project is to create new informative and compact representations of deformable objects that incorporate both analytical and learning-based approaches and encode geometric, topological, and physical information about the robot, the object, and the environment. We will do this in the context of challenging multimodal, bimanual object interaction tasks. The focus will be on physical interaction with deformable objects using multimodal feedback. To meet these objectives, we will use theoretical and computational methods together with rigorous experimental evaluation to model skilled sensorimotor behavior in bimanual robot systems.

2 424 186 €

Start date: 2020-09-01, End date: 2025-08-31

Digital signal processing (DSP) is a revolutionary paradigm shift enabling processing of physical data in the digital domain where design and implementation are considerably simplified. However, state-of-the-art analog-to-digital convertors (ADCs) preclude high-rate wideband sampling and processing with low cost and energy consumption, presenting a major bottleneck. This is mostly due to a traditional assumption that sampling must be performed at the Nyquist rate, that is, twice the signal bandwidth. Modern applications including communications, medical imaging, radar and more use signals with high bandwidth, resulting in prohibitively large Nyquist rates. Our ambitious goal is to introduce a paradigm shift in ADC design that will enable systems capable of low-rate, wideband sensing and low-rate DSP. While DSP has a rich history in exploiting structure to reduce dimensionality and perform efficient parameter extraction, current ADCs do not exploit such knowledge. We challenge current practice that separates the sampling stage from the processing stage and exploit structure in analog signals already in the ADC, to drastically reduce the sampling and processing rates. Our preliminary data shows that this allows substantial savings in sampling and processing rates --- we show rate reduction of 1/28 in ultrasound imaging, and 1/30 in radar detection. To achieve our overreaching goal we focus on three interconnected objectives -- developing the 1) theory 2) hardware and 3) applications of sub-Nyquist sampling. Our methodology ties together two areas on the frontier of signal processing: compressed sensing (CS), focused on finite length vectors, and analog sampling. Our research plan also inherently relies on advances in several other important areas within signal processing and combines multi-disciplinary research at the intersection of signal processing, information theory, optimization, estimation theory and hardware design.

2 400 000 €

Start date: 2015-08-01, End date: 2021-06-30

Immune systems are highly variable, but the sources of this variation are poorly understood. Genetic variation only explains a minor fraction of this, and we are unable to accurately predict the risk of immune mediated disease or severe infection in any given individual. I recently found that immune cells and proteins in healthy twins vary because of non-heritable influences (infections, vaccines, microbiota etc.), with only minor influences from heritable factors (Brodin, et al, Cell 2015). When and how such environmental influences shape our immune system is now important to understand. Birth represents the most transformational change in environment during the life of any individual. I propose, that environmental influences at birth, and during the first months of life could be particularly influential by imprinting on the regulatory mechanisms forming in the developing immune system. Adaptive changes in immune cell frequencies and functional states induced by early-life exposures could determine both the immune competence of the newborn, but potentially also its long-term trajectory towards immunological health or disease. Here, I propose a study of 1000 newborn children, followed longitudinally during their first 1000 days of life. By monitoring immune profiles and recording many environmental influences, we hope to understand how early life exposures can influence human immune system development. We have established a new assay based on Mass Cytometry and necessary data analysis tools (Brodin, et al, PNAS 2014), to simultaneously monitor the frequencies, phenotypes and functional states of more than 200 blood immune cell populations from only 100 microliters of blood. By monitoring environmental influences at regular follow-up visits, by questionnaires, serum measurements of infection, and gut microbiome sequencing, we aim to provide the most comprehensive analysis to date of immune system development in newborn children.

1 422 339 €

Start date: 2016-07-01, End date: 2021-06-30

Tight regulation of RNA metabolism is essential for normal brain function. This includes co and post-transcriptional regulation, which are extremely prevalent in neurons. Recently, circular RNAs (circRNAs), a highly abundant new type of regulatory non-coding RNA have been found across the animal kingdom. Two of these RNAs have been shown to act as miRNA sponges but no function is known for the thousands of other circRNAs, indicating the existence of a widespread layer of previously unknown gene regulation. The present proposal aims to comprehensively determine the role and mode of actions of circRNAs in gene expression and RNA metabolism in the fly brain. We will do so by studying their biogenesis, transport, and mechanism of action, as well as by determining the roles of circRNAs in neuronal function and behaviour. Briefly, we will: 1) identify factors involved in the biogenesis, localization, and stabilization of circRNAs; 2) determine neuro-developmental, molecular, neural and behavioural phenotypes associated with down or up regulation of specific circRNAs; 3) study the molecular mechanisms of action of circRNAs: identify circRNAs that work as miRNA sponges and determine whether circRNAs can encode proteins or act as signalling molecules and 4) perform mechanistic studies in order to determine cause-effect relationships between circRNA function and brain physiology and behaviour. The present proposal will reveal the key pathways by which circRNAs control gene expression and influence neuronal function and behaviour. Therefore it will be one of the pioneer works in the study of this new and important area of research, which we predict will fundamentally transform the study of gene expression regulation in the brain

1 971 750 €

Start date: 2016-02-01, End date: 2021-01-31

Embryogenesis is the temporal unfolding of cellular processes: proliferation, migration, differentiation, morphogenesis, apoptosis and functional specialization. These processes are well understood in specific tissues, and for specific cell types. Nevertheless, our systematic knowledge of the types of cells present in the developing and adult animal, and about their functional and lineage relationships, is limited. For example, there is no consensus on the number of cell types, and many important stem cells and progenitors remain to be discovered. Similarly, the lineage relationships between specific cell types are often poorly characterized. This is particularly true for the mammalian nervous system. We have developed (1) a reliable high-throghput method for sequencing all transcripts in 96 single cells at a time; and (2) a system for high-throughput phylogenetic lineage reconstruction. We now propose to characterize embryogenesis using a shotgun approach borrowed from genomics. Tissues will be dissected from multiple stages and dissociated to single cells. A total of 10,000 cells will be analyzed by RNA sequencing, revealing their functional cell type, their lineage relationships, and their current state (e.g. cell cycle phase). The novel approach proposed here will bring the powerful strategies pioneered in genomics into the field of developmental biology, including automation, digitization, and the random shotgun method. The data thus obtained will bring clarity to the concept of ‘cell type’; will provide a first catalog of mouse brain cell types with deep functional annotation; will provide markers for every cell type, including stem cells; and will serve as a basis for future comparative work, especially with human embryos.

1 496 032 €

Start date: 2010-11-01, End date: 2015-10-31

In contrast to mammals, newts possess exceptional capacities among vertebrates to rebuild complex structures, such as the brain. Our goal is to bridge the gap in the regenerative outcomes between newts and mammals. My group has made significant contributions towards this goal. We created a novel experimental system, which recapitulates central features of Parkinson’s disease in newts, and provides a unique model for understanding regeneration in the adult midbrain. We showed an unexpected but key feature of the newt brain that it is akin to the mammalian brain in terms of the extent of homeostatic cell turn over, but distinct in terms of its injury response, showing the regenerative capacity of the adult vertebrate brain by activating neurogenesis in normally quiescent regions. Further we established a critical role for the neurotransmitter dopamine in controlling quiescence in the midbrain, thereby preventing neurogenesis during homeostasis and terminating neurogenesis once the correct number of neurons has been produced during regeneration. Here we aim to identify key molecular pathways that regulate adult neurogenesis, to define lineage relationships between neuronal stem and progenitor cells, and to identify essential differences between newts and mammals. We will combine pharmacological modulation of neurotransmitter signaling with extensive cellular fate mapping approaches, and molecular manipulations. Ultimately we will test hypotheses derived from newt studies with mammalian systems including newt/mouse cross species complementation approaches. We expect that our findings will provide new regenerative strategies, and reveal fundamental aspects of cell fate determination, tissue growth, and tissue maintenance in normal and pathological conditions.

1 500 000 €

Start date: 2012-02-01, End date: 2017-01-31

"The dynamic nature of the brain operates at disparate time scales ranging from milliseconds to months. How do single neurons change over such long time scales? This question remains stubborn to answer in the field of brain plasticity mainly because of limited tools to study the physiology of single neurons over time in the complex environment of the brain. The research aim of this proposal is to reveal the physiological changes of single neurons in the mammalian brain over disparate time scales using time-lapse optical imaging. Specifically, we aim to establish a new team that will develop genetic and optical tools to probe the physiological activity of single neurons, in vivo. As a model system, we will study a unique neuronal population in the mammalian brain; the adult-born local neurons in the olfactory bulb. These neurons have tremendous potential to reveal how neurons develop and maintain in the intact brain because they are accessible both genetically and optically. By following the behavior of adult-born neurons in vivo we will discover how neurons mature and maintain over days and weeks. If our objectives will be met, this study has the potential to significantly ""raise the bar"" on how neuronal plasticity is studied and reveal some basic secrets of the ever changing mammalian brain."

1 750 000 €

Start date: 2008-08-01, End date: 2013-07-31

Brown adipocytes can dissipate energy in a process called adaptive thermogenesis. Whilst the classical brown adipose tissue (BAT) depots disappear during early life in humans, cold exposure can promote the appearance of brown-like adipocytes within the white adipose tissue (WAT), termed brite (brown-in-white). Increased BAT activity results in increased energy expenditure and has been correlated with leanness in humans. Hence, recruitment of brite adipocytes may constitute a promising therapeutic strategy to treat obesity and its associated metabolic diseases. Despite the beneficial metabolic properties of brown and brite adipocytes, little is known about the molecular mechanisms underlying their specification and activation in vivo. This proposal focuses on understanding the complex biology of thermogenic adipocyte biology by studying the epigenetic and transcriptional aspects of WAT britening and BAT recruitment in vivo to identify pathways of therapeutic relevance and to better define the brite precursor cells. Specific aims are to 1) investigate epigenetic and transcriptional states and heterogeneity in human and mouse adipose tissue; 2) develop a novel time-resolved method to correlate preceding chromatin states and cell fate decisions during adipose tissue remodelling; 3) identify and validate key (drugable) epigenetic and transcriptional regulators involved in brite adipocyte specification. Experimentally, I will use adipose tissue samples from human donors and mouse models, to asses at the single-cell level cellular heterogeneity, transcriptional and epigenetic states, to identify subpopulations, and to define the adaptive responses to cold or β-adrenergic stimulation. Using computational methods and in vitro and in vivo validation experiments, I will define epigenetic and transcriptional networks that control WAT britening, and develop a model of the molecular events underlying adipocyte tissue plasticity.

1 552 620 €

Start date: 2019-03-01, End date: 2024-02-29

Current control applications necessitate the treatment of systems with multiple interconnected components, rather than the traditional single component paradigm that has been studied extensively. The individual subsystems may need to fulfil different and possibly conflicting specifications in a real-time manner. At the same time, they may need to fulfill coupled constraints that are defined as relations between their states. Towards this end, the need for methods for decentralized control at the continuous level and planning at the task level becomes apparent. We aim here towards unification of these two complementary approaches. Existing solutions rely on a top down centralized approach. We instead consider here a decentralized, bottom-up solution to the problem. The approach relies on three layers of interaction. In the first layer, agents aim at coordinating in order to fulfil their coupled constraints with limited communication exchange of their state information and design of appropriate feedback controllers; in the second layer, agents coordinate in order to mutually satisfy their discrete tasks through exchange of the corresponding plans in the form of automata; in the third and most challenging layer, the communication exchange for coordination now includes both continuous state and discrete plan/abstraction information. The results will be demonstrated in a scenario involving multiple (possibly human) users and multiple robots. The unification will yield a completely decentralized system, in which the bottom up approach to define tasks, the consideration of coupled constraints and their combination towards distributed hybrid control and planning in a coordinated fashion require for new ways of thinking and approaches to analysis and constitute the proposal a beyond the SoA and groundbreaking approach to the fields of control and computer science.

1 498 729 €

Start date: 2015-03-01, End date: 2020-02-29

My objective is to understand the physiologic and medical importance of the posttranslational processing of CAAX proteins (e.g., K-RAS and prelamin A) and to define the suitability of the CAAX protein processing enzymes as therapeutic targets for the treatment of cancer and progeria. CAAX proteins undergo three posttranslational processing steps at a carboxyl-terminal CAAX motif. These processing steps, which are mediated by four different enzymes (FTase, GGTase-I, RCE1, and ICMT), increase the hydrophobicity of the carboxyl terminus of the protein and thereby facilitate interactions with membrane surfaces. Somatic mutations in K-RAS deregulate cell growth and are etiologically involved in the pathogenesis of many forms of cancer. A mutation in prelamin A causes Hutchinson-Gilford progeria syndrome—a pediatric progeroid syndrome associated with misshaped cell nuclei and a host of aging-like disease phenotypes. One strategy to render the mutant K-RAS and prelamin A less harmful is to interfere with their ability to bind to membrane surfaces (e.g., the plasma membrane and the nuclear envelope). This could be accomplished by inhibiting the enzymes that modify the CAAX motif. My Specific Aims are: (1) To define the suitability of the CAAX processing enzymes as therapeutic targets in the treatment of K-RAS-induced lung cancer and leukemia; and (2) To test the hypothesis that inactivation of FTase or ICMT will ameliorate disease phenotypes of progeria. I have developed genetic strategies to produce lung cancer or leukemia in mice by activating an oncogenic K-RAS and simultaneously inactivating different CAAX processing enzymes. I will also inactivate several CAAX processing enzymes in mice with progeria—both before the emergence of phenotypes and after the development of advanced disease phenotypes. These experiments should reveal whether the absence of the different CAAX processing enzymes affects the onset, progression, or regression of cancer and progeria.

1 689 600 €

Start date: 2008-06-01, End date: 2013-05-31

Modern cryptography has deeply rooted connections with computational complexity theory and other areas of computer science. This proposal suggests to explore several {\em new connections} between questions in cryptography and questions from other domains, including computational complexity, coding theory, and even the natural sciences. The project is expected to broaden the impact of ideas from cryptography on other domains, and on the other hand to benefit cryptography by applying tools from other domains towards better solutions for central problems in cryptography.

1 459 703 €

Start date: 2010-12-01, End date: 2015-11-30

Cancer progression, characterized by uncontrolled proliferation and motility of cells, is a complex and deadly process. Integrins, a major cell surface adhesion receptor family, are transmembrane proteins known to regulate cell behaviour by transducing extracellular signals to cytoplasmic protein complexes. We and others have shown that recruitment of specific protein complexes by the cytoplasmic domains of integrins is important in tumorigenesis. Here our aim is to study three interrelated processes in cancer progression which involve integrin signalling, but which have not been elucidated earlier at all. 1) Integrins in cell division (cytokinesis). Since coordinated action of the cytoskeleton and membranes is needed both for cell division and motility, shared integrin functions can regulate both events. 2) Dynamic integrin signalosomes at the leading edge of invading cells. Spatially and temporally regulated, integrin-protein complexes at the front of infiltrating cells are likely to dictate the movement of cancer cells in tissues. 3) Transmembrane segments of integrins as scaffolds for integrin signalling. In addition to cytosolic proteins, integrins most likely interact with proteins within the membrane resulting into new signalling modalities. In this proposal we will use innovative, modern and even unconventional techniques (such as RNAi and live-cell arrays detecting integrin traffic, cell motility and multiplication, laser-microdissection, proteomics and bacterial-two-hybrid screens) to unravel these new integrin functions, for which we have preliminary evidence. Each project will give fundamentally novel mechanistic insight into the role of integrins in cancer. Moreover, these interdisciplinary new openings will increase our understanding in cancer progression in general and will open new possibilities for therapeutic intervention targeting both cancer proliferation and dissemination in the body.

1 529 369 €

Start date: 2008-08-01, End date: 2013-07-31

Aneuploidy, an imbalanced number of chromosomes or chromosome arms, is a distinct feature of cancer. Recent years have seen conceptual, methodological and technical advances in the field of cancer aneuploidy research, but we are just beginning to scratch the surface of the underlying biology, and the potential vulnerabilities of aneuploid cancer cells remain under-explored. Cancer aneuploidy is therefore a biological enigma and a missed opportunity for cancer therapy. Identifying the “Achilles heels” of aneuploidy remains a holy grail of cancer research. However, current models of aneuploidy fail to fully recapitulate the cellular consequences of aneuploidy in cancer, thus compromising the identification of aneuploidy-induced cellular vulnerabilities. The time is ripe to tackle cancer aneuploidy with state-of-the-art genomic and functional approaches. In this project, I propose to address the following key questions: 1) What forces shape the evolution of aneuploidy in tumors? We will integrate in silico analyses of clinical data, in vitro modeling in isogenic human cell lines, and in vivo experiments in mice, to elucidate how various cellular contexts shape the tumor aneuploidy landscape. 2) What cellular vulnerabilities are induced by aneuploidy? We will combine isogenic cell lines with large-scale genetic and chemical perturbation screens, in order to identify, validate, and mechanistically dissect vulnerabilities induced by aneuploidy in human cancer cells. These research aims fall well within my unique expertise. I mapped various aneuploidy landscapes and developed innovative experimental and computational tools for studying cancer aneuploidy. A successful completion of the project will shed light on the context-dependent cellular consequences of aneuploidy in cancer and provide proof-of-concept for its potential targeting. Ultimately, identifying aneuploidy-specific vulnerabilities will pave the way for the therapeutic exploitation of this hallmark of cancer.

1 612 500 €

Start date: 2021-10-01, End date: 2026-09-30

An important form of negotiation is argumentation. This is the ability to argue and to persuade the other party to accept a desired agreement, to acquire or give information, to coordinate goals and actions, and to find and verify evidence. This is a key capability in negotiating with humans. While automated negotiations between software agents can often exchange offers and counteroffers, humans require persuasion. This challenges the design of agents arguing with people, with the objective that the outcome of the negotiation will meet the preferences of the arguer agent. CAP’s objective is to enable automated agents to argue and persuade humans. To achieve this, we intend to develop the following key components: 1) The extension of current game theory models of persuasion and bargaining to more realistic settings, 2) Algorithms and heuristics for generation and evaluation of arguments during negotiation with people, 3) Algorithms and heuristics for managing inconsistent views of the negotiation environment, and decision procedures for revelation, signalling, and requesting information, 4) The revision and update of the agent’s mental state and incorporation of social context, 5) Identifying strategies for expressing emotions in negotiations, 6) Technology for general opponent modelling from sparse and noisy data. To demonstrate the developed methods, we will implement two training systems for people to improve their interviewing capabilities, and for training negotiators in inter-culture negotiations. CAP will revolutionise the state of the art of automated systems negotiating with people. It will also create breakthroughs in the research of multi-agent systems in general, and will change paradigms by providing new directions for the way computers interact with people.

2 334 057 €

Start date: 2011-07-01, End date: 2016-06-30

Recent ground-breaking studies by my team and others demonstrated that latent heart regeneration machinery can be awakened even in adult mammals. My lab’s main contribution is the identification of two, apparently different, molecular mechanisms for augmenting cardiac regeneration in adult mice. The first requires transient activation of ErbB2 signalling in cardiomyocytes and the second involves extra cellular matrix-driven signalling by the proteoglycan agrin. Impressively, both mechanisms promote a major regenerative response that, in turn, enhances cardiac repair. In CardHeal we will use the two powerful regenerative models to obtain a holistic view of cardiac regeneration and repair mechanisms in mammals (mice and pigs). In Aim 1, we will explore the molecular mechanisms underlying our discovery that transient activation of ErbB2 in adult cardiomyocytes results in massive cardiomyocyte dedifferentiation and proliferation followed by new vessels formation, scar resolution and functional cardiac repair. Specific objectives focus on ErbB2-Yap/Hippo signalling during cardiac regeneration; ErbB2 activation in a chronic heart failure model; ErbB2-induced regenerative EMT-like process; and cardiomyocyte re-differentiation. In Aim 2, we will investigate the therapeutic effects of agrin, whose administration into injured hearts of mice and pigs elicits a significant regenerative response. Specific objectives are matrix-related cardiac regenerative cues, modulation of the immune response, angiogenesis, matrix remodeling, and developing a preclinical, large animal model to study agrin efficacy for cardiac repair. Interrogating the differences and similarities between our two regenerative models should give us a detailed roadmap for cardiac regenerative medicine by providing deeper knowledge of the regenerative process in the heart and pointing to novel targets for cardiac repair in human patients.

2 268 750 €

Start date: 2018-06-01, End date: 2023-05-31

Social-science explanations for rising wage inequality have reached a dead end. Most economists argue that computerization has been primarily responsible, while on the other side of the argument are sociologists and political scientists who stress the role of political forces in the evolution process of wages. I would like to use my knowledge and experience to come up with an original theory on the complex dynamics between technology and politics in order to solve two unsettled questions regarding the role of computerization in rising wage inequality: First, how can computerization, which diffused simultaneously in rich countries, explain the divergent inequality trends in Europe and the United States? Second, what are the mechanisms behind the well-known observed positive correlation between computers and earnings? To answer the first question, I develop a new institutional agenda stating that politics, broadly defined, mitigates the effects of technological change on wages by stimulating norms of fair pay and equity. To answer the second question, I propose a truly novel perspective that conceptualizes the earnings advantage that derives from computerization around access to and control of information on the production process. Capitalizing on this new perspective, I develop a new approach to measuring computerization to capture the form of workers’ interaction with computers at work, and build a research strategy for analysing the effect of computerization on wages across countries and workplaces, and over time. This research project challenges the common understanding of technology’s role in producing economic inequality, and would thereby significantly impact all of the abovementioned disciplines, which are debating over the upswing in wage inequality, as well as public policy, which discusses what should be done to confront the resurgence of income inequality.

1 495 091 €

Start date: 2016-09-01, End date: 2021-08-31

Bacterial biofilms are the primary cause of chronic infections and of resulting infection relapses. To be able to interfere with bacterial persistence it is vital to understand the molecular details of biofilm formation and to define how motile planktonic cells transit into surface-grown communities. The nucleotide second messenger cyclic di-guanosinemonophosphate (cdGMP) has emerged as a central regulatory factor governing bacterial surface adaptation and biofilm formation. Although cdGMP signaling may well represent the Achilles heel of bacterial communities, cdGMP networks in bacterial pathogens are exquisitely complex and an integrated cellular system to uncover the details of cdGMP dynamics is missing. To quantitatively describe cdGMP signaling we propose to exploit Caulobacter crescentus, an organism with a simple bimodal life-style that integrates the sessile-motile switch into its asymmetric division cycle. We aim to: 1) identify the role and regulation of all diguanylate cyclases and phosphodiesterases that contribute to the asymmetric cellular program with the goal to model the temporal and spatial distribution of cdGMP during development; 2) identify and characterize cdGMP effectors, their downstream targets and cellular pathways; 3) elucidate how cdGMP coordinates cell differentiation with cell growth and propagation; 4) unravel the role of cdGMP as an allosteric regulator in mechanosensation and in rapid adaptation of bacteria to growth on surfaces; 5) develop novel tools to quantitatively describe cdGMP network dynamics as the basis for mathematical modeling that provides the predictive power to experimentally test and refine important network parameters. We propose a multidisciplinary research program at the forefront of bacterial signal transduction that will provide the molecular and conceptual framework for a rapidly growing research field of second messenger signaling in pathogenic bacteria.

2 496 000 €

Start date: 2013-05-01, End date: 2018-04-30

Cell fusion is critical for fertilization and development, for instance underlying muscle or bone formation. Cell fusion may also play important roles in regeneration and cancer. A conceptual understanding is emerging that cell fusion requires cell-cell communication, polarization of the cells towards each other, and assembly of a fusion machinery, in which an actin-based structure promotes membrane juxtaposition and fusogenic factors drive membrane fusion. However, in no single system have the molecular nature of all these parts been described, and thus the molecular basis of cell fusion remains poorly understood. This proposal aims to depict the complete fusion process in a single organism, using the simple yeast model Schizosaccharomyces pombe, which has a long track record of discoveries in fundamental cellular processes. These haploid cells, which fuse to generate a diploid zygote, use highly conserved mechanisms of cell-cell communication (through pheromones and GPCR signaling), cell polarization (centred around the small GTPase Cdc42) and fusion. Indeed, we recently showed that these cells assemble an actin-based fusion structure, dubbed the actin fusion focus. Our five aims probe the molecular nature of, and the links between, signaling, polarization and the fusion machinery from initiation to termination of the process. These are: 1: To define the roles and feedback regulation of Cdc42 during cell fusion 2: To understand the molecular mechanisms of actin fusion focus formation 3: To identify the fusogen(s) promoting membrane fusion 4: To probe the GPCR signal for fusion initiation 5: To define the mechanism of fusion termination By combining genetic, optogenetic, biochemical, live-imaging, synthetic and modeling approaches, this project will bring a molecular and conceptual understanding of cell fusion. This work will have far-ranging relevance for cell polarization, cytoskeletal organization, cell signalling and communication, and cell fate regulation.

1 999 956 €

Start date: 2016-10-01, End date: 2021-09-30

The mammalian brain is assembled from thousands of neuronal cell types that are organized into distinct circuits to perform behaviourally relevant computations. To gain mechanistic insights about brain function and to treat specific diseases of the nervous system it is crucial to understand what these local circuits are computing and how they achieve these computations. By examining the structure and function of a few genetically identified and experimentally accessible neural circuits we plan to address fundamental questions about the functional architecture of neural circuits. First, are cell types assigned to a unique functional circuit with a well-defined function or do they participate in multiple circuits (“multitasking cell types”), adjusting their role depending on the state of these circuits? Second, does a neural circuit perform “a single computation” or depending on the information content of its inputs can it carry out radically different functions? Third, how, among the large number of other cell types, do the cells belonging to the same functional circuit connect together during development? We use the mouse retina as a model system to address these questions. Finally, we will study the structure and function of a specialised neural circuit in the human fovea that enables humans to read. We predict that our insights into the mechanism of multitasking, network switches and the development of selective connectivity will be instructive to study similar phenomena in other brain circuits. Knowledge of the structure and function of the human fovea will open up new opportunities to correlate human retinal function with human visual behaviour and our genetic technologies to study human foveal function will allow us and others to design better strategies for restoring vision for the blind.

1 499 000 €

Start date: 2010-11-01, End date: 2015-10-31

One promising theoretical framework to explain the function of cortex is predictive processing. It postulates that cortex functions by maintaining an internal model, or internal representation, of the world through a comparison of predictions based on this internal model with incoming sensory information. Implementing predictive processing in a cortical circuit would require a set of distinct functional cell types. These would include neurons that compute a difference between top-down predictions and bottom-up input, referred to as prediction error neurons, and a separate population of neurons that integrate the output of prediction error neurons to maintain an internal representation of the world. This research proposal will test the framework of predictive processing and identify different putative circuit elements and cell types that are thought to form the circuit in mouse visual cortex. We will use a combination of physiological recordings, optogenetic manipulations of neural activity, and gene expression measurements to determine the cell types that have functional responses consistent with different prediction errors, as well as those coding for the internal representation. Identifying the circuit elements underlying predictive processing in cortex may reveal a strategy to bias processing either towards top-down or bottom-up drive when the balance between the two is perturbed, as may be the case in neuropsychiatric disorders.

2 000 000 €

Start date: 2020-02-01, End date: 2025-01-31

"Centrioles are critical for the formation of cilia, flagella and centrosomes, as well as for human health. The mechanisms governing centriole formation constitute a long-standing question in cell biology. We will pursue an innovative multidisciplinary research program to gain further insight into these mechanisms, using human cells, C. elegans and Trichonympha as model systems. This program is expected to also have a major impact by contributing a novel cell free assay to the field, thus paving the way towards making synthetic centrioles. Six specific aims will be pursued: 1) Deciphering HsSAS-6/STIL distribution and dynamics. We will use super-resolution microscopy, molecular counting, photoconversion and FCS to further characterize these two key components required for centriole formation in human cells. 2) The SAS-6 ring model as a tool to redirect centriole organization. Utilizing predictions from the SAS-6 ring model, we will assay the consequences for centrioles and cilia of altering the diameter and symmetry of the structure. 3) Determining the architecture of C. elegans centrioles. We will conduct molecular counting and cryo-ET of purified C. elegans centrioles to determine if they contain a spiral or a cartwheel, as well as identify SAS-6-interacting components. 4) Comprehensive 3D map and proteomics of Trichonympha centriole. We will obtain a ~35 Å 3D map of the complete T. agilis centriole, perform proteomic analysis to identify its constituents and test their function using RNAi. 5) Regulation of cartwheel height and centriole length. We will explore whether cartwheel height is set by SAS-6 proteins and perform screens in human cells to identify novel components regulating cartwheel height and centriole length. 6) Novel cell free assay for cartwheel assembly and centriole formation. Using SAS-6 proteins on a lipid monolayer as starting point, we will develop and utilize a cell-free assay to reconstitute cartwheel assembly and centriole format"

2 499 270 €

Start date: 2014-04-01, End date: 2019-03-31