Project acronym Amygdala Circuits
Project Amygdala Circuits for Appetitive Conditioning
Researcher (PI) Andreas Luthi
Host Institution (HI) FRIEDRICH MIESCHER INSTITUTE FOR BIOMEDICAL RESEARCH FONDATION
Country Switzerland
Call Details Advanced Grant (AdG), LS5, ERC-2014-ADG
Summary The project outlined here addresses the fundamental question how the brain encodes and controls behavior. While we have a reasonable understanding of the role of entire brain areas in such processes, and of mechanisms at the molecular and synaptic levels, there is a big gap in our knowledge of how behavior is controlled at the level of defined neuronal circuits.
In natural environments, chances for survival depend on learning about possible aversive and appetitive outcomes and on the appropriate behavioral responses. Most studies addressing the underlying mechanisms at the level of neuronal circuits have focused on aversive learning, such as in Pavlovian fear conditioning. Understanding how activity in defined neuronal circuits mediates appetitive learning, as well as how these circuitries are shared and interact with aversive learning circuits, is a central question in the neuroscience of learning and memory and the focus of this grant application.
Using a multidisciplinary approach in mice, combining behavioral, in vivo and in vitro electrophysiological, imaging, optogenetic and state-of-the-art viral circuit tracing techniques, we aim at dissecting the neuronal circuitry of appetitive Pavlovian conditioning with a focus on the amygdala, a key brain region important for both aversive and appetitive learning. Ultimately, elucidating these mechanisms at the level of defined neurons and circuits is fundamental not only for an understanding of memory processes in the brain in general, but also to inform a mechanistic approach to psychiatric conditions associated with amygdala dysfunction and dysregulated emotional responses including anxiety and mood disorders.
Summary
The project outlined here addresses the fundamental question how the brain encodes and controls behavior. While we have a reasonable understanding of the role of entire brain areas in such processes, and of mechanisms at the molecular and synaptic levels, there is a big gap in our knowledge of how behavior is controlled at the level of defined neuronal circuits.
In natural environments, chances for survival depend on learning about possible aversive and appetitive outcomes and on the appropriate behavioral responses. Most studies addressing the underlying mechanisms at the level of neuronal circuits have focused on aversive learning, such as in Pavlovian fear conditioning. Understanding how activity in defined neuronal circuits mediates appetitive learning, as well as how these circuitries are shared and interact with aversive learning circuits, is a central question in the neuroscience of learning and memory and the focus of this grant application.
Using a multidisciplinary approach in mice, combining behavioral, in vivo and in vitro electrophysiological, imaging, optogenetic and state-of-the-art viral circuit tracing techniques, we aim at dissecting the neuronal circuitry of appetitive Pavlovian conditioning with a focus on the amygdala, a key brain region important for both aversive and appetitive learning. Ultimately, elucidating these mechanisms at the level of defined neurons and circuits is fundamental not only for an understanding of memory processes in the brain in general, but also to inform a mechanistic approach to psychiatric conditions associated with amygdala dysfunction and dysregulated emotional responses including anxiety and mood disorders.
Max ERC Funding
2 497 200 €
Duration
Start date: 2016-01-01, End date: 2020-12-31
Project acronym ANOBEST
Project Structure function and pharmacology of calcium-activated chloride channels: Anoctamins and Bestrophins
Researcher (PI) Raimund Dutzler
Host Institution (HI) University of Zurich
Country Switzerland
Call Details Advanced Grant (AdG), LS1, ERC-2013-ADG
Summary 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.
Summary
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.
Max ERC Funding
2 176 000 €
Duration
Start date: 2014-02-01, End date: 2020-01-31
Project acronym astromnesis
Project The language of astrocytes: multilevel analysis to understand astrocyte communication and its role in memory-related brain operations and in cognitive behavior
Researcher (PI) Andrea Volterra
Host Institution (HI) UNIVERSITE DE LAUSANNE
Country Switzerland
Call Details Advanced Grant (AdG), LS5, ERC-2013-ADG
Summary In the 90s, two landmark observations brought to a paradigm shift about the role of astrocytes in brain function: 1) astrocytes respond to signals coming from other cells with transient Ca2+ elevations; 2) Ca2+ transients in astrocytes trigger release of neuroactive and vasoactive agents. Since then, many modulatory astrocytic actions and mechanisms were described, forming a complex - partly contradictory - picture, in which the exact roles and modes of astrocyte action remain ill defined. Our project wants to bring light into the “language of astrocytes”, i.e. into how they communicate with neurons and, ultimately, address their role in brain computations and cognitive behavior. To this end we will perform 4 complementary levels of analysis using highly innovative methodologies in order to obtain unprecedented results. We will study: 1) the subcellular organization of astrocytes underlying local microdomain communications by use of correlative light-electron microscopy; 2) the way individual astrocytes integrate inputs and control synaptic ensembles using 3D two-photon imaging, genetically-encoded Ca2+ indicators, optogenetics and electrophysiology; 3) the contribution of astrocyte ensembles to behavior-relevant circuit operations using miniaturized microscopes capturing neuronal/astrocytic population dynamics in freely-moving mice during memory tests; 4) the contribution of astrocytic signalling mechanisms to cognitive behavior using a set of new mouse lines with conditional, astrocyte-specific genetic modification of signalling pathways. We expect that this combination of groundbreaking ideas, innovative technologies and multilevel analysis makes our project highly attractive to the neuroscience community at large, bridging aspects of molecular, cellular, systems and behavioral neuroscience, with the goal of leading from a provocative hypothesis to the conclusive demonstration of whether and how “the language of astrocytes” participates in memory and cognition.
Summary
In the 90s, two landmark observations brought to a paradigm shift about the role of astrocytes in brain function: 1) astrocytes respond to signals coming from other cells with transient Ca2+ elevations; 2) Ca2+ transients in astrocytes trigger release of neuroactive and vasoactive agents. Since then, many modulatory astrocytic actions and mechanisms were described, forming a complex - partly contradictory - picture, in which the exact roles and modes of astrocyte action remain ill defined. Our project wants to bring light into the “language of astrocytes”, i.e. into how they communicate with neurons and, ultimately, address their role in brain computations and cognitive behavior. To this end we will perform 4 complementary levels of analysis using highly innovative methodologies in order to obtain unprecedented results. We will study: 1) the subcellular organization of astrocytes underlying local microdomain communications by use of correlative light-electron microscopy; 2) the way individual astrocytes integrate inputs and control synaptic ensembles using 3D two-photon imaging, genetically-encoded Ca2+ indicators, optogenetics and electrophysiology; 3) the contribution of astrocyte ensembles to behavior-relevant circuit operations using miniaturized microscopes capturing neuronal/astrocytic population dynamics in freely-moving mice during memory tests; 4) the contribution of astrocytic signalling mechanisms to cognitive behavior using a set of new mouse lines with conditional, astrocyte-specific genetic modification of signalling pathways. We expect that this combination of groundbreaking ideas, innovative technologies and multilevel analysis makes our project highly attractive to the neuroscience community at large, bridging aspects of molecular, cellular, systems and behavioral neuroscience, with the goal of leading from a provocative hypothesis to the conclusive demonstration of whether and how “the language of astrocytes” participates in memory and cognition.
Max ERC Funding
2 513 896 €
Duration
Start date: 2014-02-01, End date: 2019-01-31
Project acronym BARRAGE
Project Cell compartmentalization, individuation and diversity
Researcher (PI) Yves Barral
Host Institution (HI) EIDGENOESSISCHE TECHNISCHE HOCHSCHULE ZUERICH
Country Switzerland
Call Details Advanced Grant (AdG), LS3, ERC-2009-AdG
Summary 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.
Summary
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.
Max ERC Funding
2 200 000 €
Duration
Start date: 2010-05-01, End date: 2015-04-30
Project acronym CCICO
Project Coupled and Competing Instabilities in Complex Oxides
Researcher (PI) Nicola Ann Spaldin
Host Institution (HI) EIDGENOESSISCHE TECHNISCHE HOCHSCHULE ZUERICH
Country Switzerland
Call Details Advanced Grant (AdG), PE3, ERC-2011-ADG_20110209
Summary "The CCICO project will build a comprehensive understanding of how proximity to previously unexplored combinations of instabilities, as well as previously unidentified types of ordering, manifest in novel behaviors, and will develop design guidelines for practical realization of new materials with such behaviors. Taking transition-metal oxides as our model systems, we will develop and apply first-principles electronic structure theory methods to explore an extensive array of new combinations of orderings, with a focus on interactions between the electronic -- Jahn-Teller, orbital and charge -- and structural -- rotations, ferroelectric and other distortions -- degrees of freedom. Our goal is to spawn a new field of study based on a novel combination of orderings in the same way that the field of multiferroics was jump-started ten years ago by our work understanding the coexistence of ferroelectricity and magnetism. Conversely, we will apply the computational tools developed in our history of studying multiferroics, particularly descriptions of proximity to structural and magnetic phase transitions, to characterizing observed behaviors such as exotic superconductivity in existing materials. In the process we will search for and characterize elusive or poorly characterized forms of order in solids, with a focus on ferrotoroidicity and emergent local dipoles. A final application is to create designer materials for solid-state experiments relevant to high-energy physics and cosmology. Promising compounds that are amenable to bulk synthesis will be made in our new oxide single-crystal growth laboratory; materials that require thin-film routes will be pursued in collaboration with colleagues."
Summary
"The CCICO project will build a comprehensive understanding of how proximity to previously unexplored combinations of instabilities, as well as previously unidentified types of ordering, manifest in novel behaviors, and will develop design guidelines for practical realization of new materials with such behaviors. Taking transition-metal oxides as our model systems, we will develop and apply first-principles electronic structure theory methods to explore an extensive array of new combinations of orderings, with a focus on interactions between the electronic -- Jahn-Teller, orbital and charge -- and structural -- rotations, ferroelectric and other distortions -- degrees of freedom. Our goal is to spawn a new field of study based on a novel combination of orderings in the same way that the field of multiferroics was jump-started ten years ago by our work understanding the coexistence of ferroelectricity and magnetism. Conversely, we will apply the computational tools developed in our history of studying multiferroics, particularly descriptions of proximity to structural and magnetic phase transitions, to characterizing observed behaviors such as exotic superconductivity in existing materials. In the process we will search for and characterize elusive or poorly characterized forms of order in solids, with a focus on ferrotoroidicity and emergent local dipoles. A final application is to create designer materials for solid-state experiments relevant to high-energy physics and cosmology. Promising compounds that are amenable to bulk synthesis will be made in our new oxide single-crystal growth laboratory; materials that require thin-film routes will be pursued in collaboration with colleagues."
Max ERC Funding
2 000 000 €
Duration
Start date: 2012-03-01, End date: 2017-02-28
Project acronym CellularBiographies
Project Global views of cell type specification and differentiation
Researcher (PI) Alexander Schier
Host Institution (HI) UNIVERSITAT BASEL
Country Switzerland
Call Details Advanced Grant (AdG), LS3, ERC-2018-ADG
Summary Each cell in our body has a specific biography that is defined by its pedigree relationship with other cells (lineage) and by its history of gene expression (trajectory). A fundamental question in cellular and developmental biology has been how the lineage and trajectory of a cell lead to its specification and differentiation. Remarkable progress in genome editing and single-cell sequencing has generated the opportunity to understand this process at global scales and single-cell resolution. We have recently developed methods to reconstruct the cellular ancestry and transcriptional trajectories of cells during embryogenesis. The resulting lineage and trajectory trees can be analyzed to gain comprehensive views of how cellular diversity arises and how differentiation leads to physiologically specialized cell types. To generate such global views of cellular development, we will: 1. Define the cellular diversity and gene expression trajectories during zebrafish embryogenesis and organogenesis. Trajectory trees will be generated from scRNA-seq data and analyzed to reconstruct the gene expression pathways underlying fate specification. 2. Reveal the relationships between lineage and transcriptional trajectories during fate specification. Lineage trees will be generated by marking cells via genome editing and combined with trajectory trees to reveal the cellular paths towards fate specification. 3. Discover the gene expression cascades that remodel cells into physiologically functional types. Cell biological modules will be identified by comparing gene enrichment in differentiation trajectories and reveal the specialized and shared mechanisms of differentiation. These studies will help provide the first comprehensive and global view of the trajectories and lineages underlying vertebrate development. Our focus is on the zebrafish model system, but the data and concepts developed in this project will be applicable to other developmental and cellular systems.
Summary
Each cell in our body has a specific biography that is defined by its pedigree relationship with other cells (lineage) and by its history of gene expression (trajectory). A fundamental question in cellular and developmental biology has been how the lineage and trajectory of a cell lead to its specification and differentiation. Remarkable progress in genome editing and single-cell sequencing has generated the opportunity to understand this process at global scales and single-cell resolution. We have recently developed methods to reconstruct the cellular ancestry and transcriptional trajectories of cells during embryogenesis. The resulting lineage and trajectory trees can be analyzed to gain comprehensive views of how cellular diversity arises and how differentiation leads to physiologically specialized cell types. To generate such global views of cellular development, we will: 1. Define the cellular diversity and gene expression trajectories during zebrafish embryogenesis and organogenesis. Trajectory trees will be generated from scRNA-seq data and analyzed to reconstruct the gene expression pathways underlying fate specification. 2. Reveal the relationships between lineage and transcriptional trajectories during fate specification. Lineage trees will be generated by marking cells via genome editing and combined with trajectory trees to reveal the cellular paths towards fate specification. 3. Discover the gene expression cascades that remodel cells into physiologically functional types. Cell biological modules will be identified by comparing gene enrichment in differentiation trajectories and reveal the specialized and shared mechanisms of differentiation. These studies will help provide the first comprehensive and global view of the trajectories and lineages underlying vertebrate development. Our focus is on the zebrafish model system, but the data and concepts developed in this project will be applicable to other developmental and cellular systems.
Max ERC Funding
2 411 440 €
Duration
Start date: 2020-01-01, End date: 2024-12-31
Project acronym CEMAS
Project Controlling and Exploring Molecular Systems at the Atomic Scale with Atomic Force Microscopy
Researcher (PI) Gerhard Meyer
Host Institution (HI) IBM RESEARCH GMBH
Country Switzerland
Call Details Advanced Grant (AdG), PE3, ERC-2011-ADG_20110209
Summary The objective of this project is to advance and use Atomic Force Microscopy (AFM) to explore the physical and chemical properties of single molecules and molecular systems with unprecedented spatial resolution. We will use AFM to develop atomically resolved molecular imaging with structural and chemical identification and investigate charge distribution and transfer in molecular systems. The AFM will allow the extension of seminal Scanning Tunneling Microscopy (STM) work on atoms/molecules on ultra-thin insulating films to thick insulating films, to control and explore single molecule chemistry processes in utmost detail. The whole work will be significantly based on the development and exploitation of novel atomic and molecular manipulation processes to control matter at the atomic scale, both for fabricating novel complex molecular nanostructures with atomic scale precision and understanding these systems, as well as for probe-tip functionalization to tailor tip-substrate interaction. Instrumental enhancements will focus on fabricating novel AFM sensors for simultaneous lateral and vertical force measurement and on developing a new original approach to increase the time resolution in AFM measurements. Due to the fundamental nature of this work we expect the long term impact of this work to be in surface science, chemistry, molecular electronics and life sciences. In the short term we expect to develop the AFM into a practical tool for chemical structure determination of unknown molecules and we will employ atomic manipulation and high resolution AFM imaging to image, modify and functionalize graphene edge structures with atomic scale precision with the prospect of exploring and developing novel molecular devices.
Summary
The objective of this project is to advance and use Atomic Force Microscopy (AFM) to explore the physical and chemical properties of single molecules and molecular systems with unprecedented spatial resolution. We will use AFM to develop atomically resolved molecular imaging with structural and chemical identification and investigate charge distribution and transfer in molecular systems. The AFM will allow the extension of seminal Scanning Tunneling Microscopy (STM) work on atoms/molecules on ultra-thin insulating films to thick insulating films, to control and explore single molecule chemistry processes in utmost detail. The whole work will be significantly based on the development and exploitation of novel atomic and molecular manipulation processes to control matter at the atomic scale, both for fabricating novel complex molecular nanostructures with atomic scale precision and understanding these systems, as well as for probe-tip functionalization to tailor tip-substrate interaction. Instrumental enhancements will focus on fabricating novel AFM sensors for simultaneous lateral and vertical force measurement and on developing a new original approach to increase the time resolution in AFM measurements. Due to the fundamental nature of this work we expect the long term impact of this work to be in surface science, chemistry, molecular electronics and life sciences. In the short term we expect to develop the AFM into a practical tool for chemical structure determination of unknown molecules and we will employ atomic manipulation and high resolution AFM imaging to image, modify and functionalize graphene edge structures with atomic scale precision with the prospect of exploring and developing novel molecular devices.
Max ERC Funding
2 496 720 €
Duration
Start date: 2011-12-01, End date: 2016-11-30
Project acronym CENDUP
Project Decoding the mechanisms of centrosome duplication
Researcher (PI) Pierre Goenczy
Host Institution (HI) ECOLE POLYTECHNIQUE FEDERALE DE LAUSANNE
Country Switzerland
Call Details Advanced Grant (AdG), LS3, ERC-2008-AdG
Summary Centrosome duplication entails the formation of a single procentriole next to each centriole once per cell cycle. The mechanisms governing procentriole formation are poorly understood and constitute a fundamental open question in cell biology. We will launch an innovative multidisciplinary research program to gain significant insight into these mechanisms using C. elegans and human cells. This research program is also expected to have a significant impact by contributing important novel assays to the field. Six specific aims will be pursued: 1) SAS-6 as a ZYG-1 substrate: mechanisms of procentriole formation in C. elegans. We will test in vivo the consequence of SAS-6 phosphorylation by ZYG-1. 2) Biochemical and structural analysis of SAS-6-containing macromolecular complexes (SAMACs). We will isolate and characterize SAMACs from C. elegans embryos and human cells, and analyze their structure using single-particle electron microscopy. 3) Novel cell-free assay for procentriole formation in human cells. We will develop such an assay and use it to test whether SAMACs can direct procentriole formation and whether candidate proteins are needed at centrioles or in the cytoplasm. 4) Mapping interactions between centriolar proteins in live human cells. We will use chemical methods developed by our collaborators to probe interactions between HsSAS-6 and centriolar proteins in a time- and space-resolved manner. 5) Functional genomic and chemical genetic screens in human cells. We will conduct high-throughput fluorescence-based screens in human cells to identify novel genes required for procentriole formation and small molecule inhibitors of this process. 6) Mechanisms underlying differential centriolar maintenance in the germline. In C. elegans, we will characterize how the sas-1 locus is required for centriole maintenance during spermatogenesis, as well as analyze centriole elimination during oogenesis and identify components needed for this process
Summary
Centrosome duplication entails the formation of a single procentriole next to each centriole once per cell cycle. The mechanisms governing procentriole formation are poorly understood and constitute a fundamental open question in cell biology. We will launch an innovative multidisciplinary research program to gain significant insight into these mechanisms using C. elegans and human cells. This research program is also expected to have a significant impact by contributing important novel assays to the field. Six specific aims will be pursued: 1) SAS-6 as a ZYG-1 substrate: mechanisms of procentriole formation in C. elegans. We will test in vivo the consequence of SAS-6 phosphorylation by ZYG-1. 2) Biochemical and structural analysis of SAS-6-containing macromolecular complexes (SAMACs). We will isolate and characterize SAMACs from C. elegans embryos and human cells, and analyze their structure using single-particle electron microscopy. 3) Novel cell-free assay for procentriole formation in human cells. We will develop such an assay and use it to test whether SAMACs can direct procentriole formation and whether candidate proteins are needed at centrioles or in the cytoplasm. 4) Mapping interactions between centriolar proteins in live human cells. We will use chemical methods developed by our collaborators to probe interactions between HsSAS-6 and centriolar proteins in a time- and space-resolved manner. 5) Functional genomic and chemical genetic screens in human cells. We will conduct high-throughput fluorescence-based screens in human cells to identify novel genes required for procentriole formation and small molecule inhibitors of this process. 6) Mechanisms underlying differential centriolar maintenance in the germline. In C. elegans, we will characterize how the sas-1 locus is required for centriole maintenance during spermatogenesis, as well as analyze centriole elimination during oogenesis and identify components needed for this process
Max ERC Funding
2 004 155 €
Duration
Start date: 2009-04-01, End date: 2014-03-31
Project acronym CFRFSS
Project Chromatin Fiber and Remodeling Factor Structural Studies
Researcher (PI) Timothy John Richmond
Host Institution (HI) EIDGENOESSISCHE TECHNISCHE HOCHSCHULE ZUERICH
Country Switzerland
Call Details Advanced Grant (AdG), LS1, ERC-2012-ADG_20120314
Summary "DNA in higher organisms is organized in a nucleoprotein complex called chromatin. The structure of chromatin is responsible for compacting DNA to fit within the nucleus and for governing its access in nuclear processes. Epigenetic information is encoded chiefly via chromatin modifications. Readout of the genetic code depends on chromatin remodeling, a process actively altering chromatin structure. An understanding of the hierarchical structure of chromatin and of structurally based, remodeling mechanisms will have enormous impact for developments in medicine.
Following our high resolution structure of the nucleosome core particle, the fundamental repeating unit of chromatin, we have endeavored to determine the structure of the chromatin fiber. We showed with our X-ray structure of a tetranucleosome how nucleosomes could be organized in the fiber. Further progress has been limited by structural polymorphism and crystal disorder, but new evidence on the in vivo spacing of nucleosomes in chromatin should stimulate more advances. Part A of this application describes how we would apply these new findings to our cryo-electron microscopy study of the chromatin fiber and to our crystallographic study of a tetranucleosome containing linker histone.
Recently, my laboratory succeeded in providing the first structurally based mechanism for nucleosome spacing by a chromatin remodeling factor. We combined the X-ray structure of ISW1a(ATPase) bound to DNA with cryo-EM structures of the factor bound to two different nucleosomes to build a model showing how this remodeler uses a dinucleosome, not a mononucleosome, as its substrate. Our results from a functional assay using ISW1a further justified this model. Part B of this application describes how we would proceed to the relevant cryo-EM and X-ray structures incorporating dinucleosomes. Our recombinant ISW1a allows us to study in addition the interaction of the ATPase domain with nucleosome substrates."
Summary
"DNA in higher organisms is organized in a nucleoprotein complex called chromatin. The structure of chromatin is responsible for compacting DNA to fit within the nucleus and for governing its access in nuclear processes. Epigenetic information is encoded chiefly via chromatin modifications. Readout of the genetic code depends on chromatin remodeling, a process actively altering chromatin structure. An understanding of the hierarchical structure of chromatin and of structurally based, remodeling mechanisms will have enormous impact for developments in medicine.
Following our high resolution structure of the nucleosome core particle, the fundamental repeating unit of chromatin, we have endeavored to determine the structure of the chromatin fiber. We showed with our X-ray structure of a tetranucleosome how nucleosomes could be organized in the fiber. Further progress has been limited by structural polymorphism and crystal disorder, but new evidence on the in vivo spacing of nucleosomes in chromatin should stimulate more advances. Part A of this application describes how we would apply these new findings to our cryo-electron microscopy study of the chromatin fiber and to our crystallographic study of a tetranucleosome containing linker histone.
Recently, my laboratory succeeded in providing the first structurally based mechanism for nucleosome spacing by a chromatin remodeling factor. We combined the X-ray structure of ISW1a(ATPase) bound to DNA with cryo-EM structures of the factor bound to two different nucleosomes to build a model showing how this remodeler uses a dinucleosome, not a mononucleosome, as its substrate. Our results from a functional assay using ISW1a further justified this model. Part B of this application describes how we would proceed to the relevant cryo-EM and X-ray structures incorporating dinucleosomes. Our recombinant ISW1a allows us to study in addition the interaction of the ATPase domain with nucleosome substrates."
Max ERC Funding
2 500 000 €
Duration
Start date: 2013-01-01, End date: 2017-12-31
Project acronym CHANGE
Project New CHallenges for (adaptive) PDE solvers: the interplay of ANalysis and GEometry
Researcher (PI) Annalisa BUFFA
Host Institution (HI) ECOLE POLYTECHNIQUE FEDERALE DE LAUSANNE
Country Switzerland
Call Details Advanced Grant (AdG), PE1, ERC-2015-AdG
Summary The simulation of Partial Differential Equations (PDEs) is an indispensable tool for innovation in science and technology.
Computer-based simulation of PDEs approximates unknowns defined on a geometrical entity such as the computational domain with all of its properties. Mainly due to historical reasons, geometric design and numerical methods for PDEs have been developed independently, resulting in tools that rely on different representations of the same objects.
CHANGE aims at developing innovative mathematical tools for numerically solving PDEs and for geometric modeling and processing, the final goal being the definition of a common framework where geometrical entities and simulation are coherently integrated and where adaptive methods can be used to guarantee optimal use of computer resources, from the geometric description to the simulation.
We will concentrate on two classes of methods for the discretisation of PDEs that are having growing impact:
isogeometric methods and variational methods on polyhedral partitions. They are both extensions of standard finite elements enjoying exciting features, but both lack of an ad-hoc geometric modelling counterpart.
We will extend numerical methods to ensure robustness on the most general geometric models, and we will develop geometric tools to construct, manipulate and refine such models. Based on our tools, we will design an innovative adaptive framework, that jointly exploits multilevel representation of geometric entities and PDE unknowns.
Moreover, efficient algorithms call for efficient implementation: the issue of the optimisation of our algorithms on modern computer architecture will be addressed.
Our research (and the team involved in the project) will combine competencies in computer science, numerical analysis, high performance computing, and computational mechanics. Leveraging our innovative tools, we will also tackle challenging numerical problems deriving from bio-mechanical applications.
Summary
The simulation of Partial Differential Equations (PDEs) is an indispensable tool for innovation in science and technology.
Computer-based simulation of PDEs approximates unknowns defined on a geometrical entity such as the computational domain with all of its properties. Mainly due to historical reasons, geometric design and numerical methods for PDEs have been developed independently, resulting in tools that rely on different representations of the same objects.
CHANGE aims at developing innovative mathematical tools for numerically solving PDEs and for geometric modeling and processing, the final goal being the definition of a common framework where geometrical entities and simulation are coherently integrated and where adaptive methods can be used to guarantee optimal use of computer resources, from the geometric description to the simulation.
We will concentrate on two classes of methods for the discretisation of PDEs that are having growing impact:
isogeometric methods and variational methods on polyhedral partitions. They are both extensions of standard finite elements enjoying exciting features, but both lack of an ad-hoc geometric modelling counterpart.
We will extend numerical methods to ensure robustness on the most general geometric models, and we will develop geometric tools to construct, manipulate and refine such models. Based on our tools, we will design an innovative adaptive framework, that jointly exploits multilevel representation of geometric entities and PDE unknowns.
Moreover, efficient algorithms call for efficient implementation: the issue of the optimisation of our algorithms on modern computer architecture will be addressed.
Our research (and the team involved in the project) will combine competencies in computer science, numerical analysis, high performance computing, and computational mechanics. Leveraging our innovative tools, we will also tackle challenging numerical problems deriving from bio-mechanical applications.
Max ERC Funding
2 199 219 €
Duration
Start date: 2016-10-01, End date: 2021-09-30
