Project acronym A-FRO
Project Actively Frozen - contextual modulation of freezing and its neuronal basis
Researcher (PI) Marta de Aragao Pacheco Moita
Host Institution (HI) FUNDACAO D. ANNA SOMMER CHAMPALIMAUD E DR. CARLOS MONTEZ CHAMPALIMAUD
Country Portugal
Call Details Consolidator Grant (CoG), LS5, ERC-2018-COG
Summary When faced with a threat, an animal must decide whether to freeze, reducing its chances of being noticed, or to flee to the safety of a refuge. Animals from fish to primates choose between these two alternatives when confronted by an attacking predator, a choice that largely depends on the context in which the threat occurs. Recent work has made strides identifying the pre-motor circuits, and their inputs, which control freezing behavior in rodents, but how contextual information is integrated to guide this choice is still far from understood. We recently found that fruit flies in response to visual looming stimuli, simulating a large object on collision course, make rapid freeze/flee choices that depend on the social and spatial environment, and the fly’s internal state. Further, identification of looming detector neurons was recently reported and we identified the descending command neurons, DNp09, responsible for freezing in the fly. Knowing the sensory input and descending output for looming-evoked freezing, two environmental factors that modulate its expression, and using a genetically tractable system affording the use of large sample sizes, places us in an unique position to understand how a information about a threat is integrated with cues from the environment to guide the choice of whether to freeze (our goal). To assess how social information impinges on the circuit for freezing, we will examine the sensory inputs and neuromodulators that mediate this process, mapping their connections to DNp09 neurons (Aim 1). We ask whether learning is required for the spatial modulation of freezing, which cues flies are using to discriminate different places and which brain circuits mediate this process (Aim 2). Finally, we will study how activity of DNp09 neurons drives freezing (Aim 3). This project will provide a comprehensive understanding of the mechanism of freezing and its modulation by the environment, from single neurons to behaviour.
Summary
When faced with a threat, an animal must decide whether to freeze, reducing its chances of being noticed, or to flee to the safety of a refuge. Animals from fish to primates choose between these two alternatives when confronted by an attacking predator, a choice that largely depends on the context in which the threat occurs. Recent work has made strides identifying the pre-motor circuits, and their inputs, which control freezing behavior in rodents, but how contextual information is integrated to guide this choice is still far from understood. We recently found that fruit flies in response to visual looming stimuli, simulating a large object on collision course, make rapid freeze/flee choices that depend on the social and spatial environment, and the fly’s internal state. Further, identification of looming detector neurons was recently reported and we identified the descending command neurons, DNp09, responsible for freezing in the fly. Knowing the sensory input and descending output for looming-evoked freezing, two environmental factors that modulate its expression, and using a genetically tractable system affording the use of large sample sizes, places us in an unique position to understand how a information about a threat is integrated with cues from the environment to guide the choice of whether to freeze (our goal). To assess how social information impinges on the circuit for freezing, we will examine the sensory inputs and neuromodulators that mediate this process, mapping their connections to DNp09 neurons (Aim 1). We ask whether learning is required for the spatial modulation of freezing, which cues flies are using to discriminate different places and which brain circuits mediate this process (Aim 2). Finally, we will study how activity of DNp09 neurons drives freezing (Aim 3). This project will provide a comprehensive understanding of the mechanism of freezing and its modulation by the environment, from single neurons to behaviour.
Max ERC Funding
1 969 750 €
Duration
Start date: 2019-02-01, End date: 2024-01-31
Project acronym ADHESWITCHES
Project Adhesion switches in cancer and development: from in vivo to synthetic biology
Researcher (PI) Mari Johanna Ivaska
Host Institution (HI) TURUN YLIOPISTO
Country Finland
Call Details Consolidator Grant (CoG), LS3, ERC-2013-CoG
Summary Integrins are transmembrane cell adhesion receptors controlling cell proliferation and migration. Our objective is to gain fundamentally novel mechanistic insight into the emerging new roles of integrins in cancer and to generate a road map of integrin dependent pathways critical in mammary gland development and integrin signalling thus opening new targets for therapeutic interventions. We will combine an in vivo based translational approach with cell and molecular biological studies aiming to identify entirely novel concepts in integrin function using cutting edge techniques and synthetic-biology tools.
The specific objectives are:
1) Integrin inactivation in branching morphogenesis and cancer invasion. Integrins regulate mammary gland development and cancer invasion but the role of integrin inactivating proteins in these processes is currently completely unknown. We will investigate this using genetically modified mice, ex-vivo organoid models and human tissues with the aim to identify beneficial combinational treatments against cancer invasion.
2) Endosomal adhesomes – cross-talk between integrin activity and integrin “inside-in signaling”. We hypothesize that endocytosed active integrins engage in specialized endosomal signaling that governs cell survival especially in cancer. RNAi cell arrays, super-resolution STED imaging and endosomal proteomics will be used to investigate integrin signaling in endosomes.
3) Spatio-temporal co-ordination of adhesion and endocytosis. Several cytosolic proteins compete for integrin binding to regulate activation, endocytosis and recycling. Photoactivatable protein-traps and predefined matrix micropatterns will be employed to mechanistically dissect the spatio-temporal dynamics and hierarchy of their recruitment.
We will employ innovative and unconventional techniques to address three major unanswered questions in the field and significantly advance our understanding of integrin function in development and cancer.
Summary
Integrins are transmembrane cell adhesion receptors controlling cell proliferation and migration. Our objective is to gain fundamentally novel mechanistic insight into the emerging new roles of integrins in cancer and to generate a road map of integrin dependent pathways critical in mammary gland development and integrin signalling thus opening new targets for therapeutic interventions. We will combine an in vivo based translational approach with cell and molecular biological studies aiming to identify entirely novel concepts in integrin function using cutting edge techniques and synthetic-biology tools.
The specific objectives are:
1) Integrin inactivation in branching morphogenesis and cancer invasion. Integrins regulate mammary gland development and cancer invasion but the role of integrin inactivating proteins in these processes is currently completely unknown. We will investigate this using genetically modified mice, ex-vivo organoid models and human tissues with the aim to identify beneficial combinational treatments against cancer invasion.
2) Endosomal adhesomes – cross-talk between integrin activity and integrin “inside-in signaling”. We hypothesize that endocytosed active integrins engage in specialized endosomal signaling that governs cell survival especially in cancer. RNAi cell arrays, super-resolution STED imaging and endosomal proteomics will be used to investigate integrin signaling in endosomes.
3) Spatio-temporal co-ordination of adhesion and endocytosis. Several cytosolic proteins compete for integrin binding to regulate activation, endocytosis and recycling. Photoactivatable protein-traps and predefined matrix micropatterns will be employed to mechanistically dissect the spatio-temporal dynamics and hierarchy of their recruitment.
We will employ innovative and unconventional techniques to address three major unanswered questions in the field and significantly advance our understanding of integrin function in development and cancer.
Max ERC Funding
1 887 910 €
Duration
Start date: 2014-05-01, End date: 2019-04-30
Project acronym ANTILEAK
Project Development of antagonists of vascular leakage
Researcher (PI) Pipsa SAHARINEN
Host Institution (HI) HELSINGIN YLIOPISTO
Country Finland
Call Details Consolidator Grant (CoG), LS4, ERC-2017-COG
Summary 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.
Summary
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.
Max ERC Funding
1 999 770 €
Duration
Start date: 2018-05-01, End date: 2023-04-30
Project acronym BHIVE
Project Bio-derived HIgh Value polymers through novel Enzyme function
Researcher (PI) Emma Rusi Master
Host Institution (HI) AALTO KORKEAKOULUSAATIO SR
Country Finland
Call Details Consolidator Grant (CoG), LS9, ERC-2014-CoG
Summary Recent advances in systems-level study of cells and organisms have revealed the enormous potential to live more sustainably through better use of biological processes. Plants sustainably synthesize the most abundant and diverse materials on Earth. By applying recent advances in life science technology, we can better harness renewable plant resources and bioconversion processes, to develop environmentally and politically sustainable human enterprise and lifestyles. At the same time, the global market for high-value biochemicals and bioplastics from forest and agricultural sources is rapidly increasing, which presents new opportunities for forest and agricultural sectors.
The overall aim of BHIVE is to illuminate uncharted regions of genome and metagenome sequences to discover entirely new protein families that can be used to sustainably synthesize novel, high-value biomaterials from renewable plant resources. The approach will include three parallel research thrusts: 1) strategic analysis of transcriptome and metagenome sequences to identify proteins with entirely unknown function relevant to biomass (lignocellulose) transformation, 2) mapping of uncharted regions within phylogenetic trees of poorly characterized enzyme families with recognized potential to modify the chemistry and biophysical properties of plant polysaccharides, and 3) the design and development of novel enzyme screens to directly address the increasing limitations of existing assays to uncover entirely new protein functions. BHIVE will be unique in its undivided focus on characterizing lignocellulose-active proteins encoded by the 30-40% of un-annotated sequence, or genomic “dark matter”, typical of nearly all genome sequences. In this way, BHIVE tackles a key constraint to fully realizing the societal and environmental benefits of the genomics era.
Summary
Recent advances in systems-level study of cells and organisms have revealed the enormous potential to live more sustainably through better use of biological processes. Plants sustainably synthesize the most abundant and diverse materials on Earth. By applying recent advances in life science technology, we can better harness renewable plant resources and bioconversion processes, to develop environmentally and politically sustainable human enterprise and lifestyles. At the same time, the global market for high-value biochemicals and bioplastics from forest and agricultural sources is rapidly increasing, which presents new opportunities for forest and agricultural sectors.
The overall aim of BHIVE is to illuminate uncharted regions of genome and metagenome sequences to discover entirely new protein families that can be used to sustainably synthesize novel, high-value biomaterials from renewable plant resources. The approach will include three parallel research thrusts: 1) strategic analysis of transcriptome and metagenome sequences to identify proteins with entirely unknown function relevant to biomass (lignocellulose) transformation, 2) mapping of uncharted regions within phylogenetic trees of poorly characterized enzyme families with recognized potential to modify the chemistry and biophysical properties of plant polysaccharides, and 3) the design and development of novel enzyme screens to directly address the increasing limitations of existing assays to uncover entirely new protein functions. BHIVE will be unique in its undivided focus on characterizing lignocellulose-active proteins encoded by the 30-40% of un-annotated sequence, or genomic “dark matter”, typical of nearly all genome sequences. In this way, BHIVE tackles a key constraint to fully realizing the societal and environmental benefits of the genomics era.
Max ERC Funding
1 977 781 €
Duration
Start date: 2015-09-01, End date: 2020-12-31
Project acronym BIZEB
Project Bio-Imaging of Zoonotic and Emerging Bunyaviruses
Researcher (PI) Juha Huiskonen
Host Institution (HI) HELSINGIN YLIOPISTO
Country Finland
Call Details Consolidator Grant (CoG), LS1, ERC-2014-CoG
Summary We aim to understand host cell entry of enveloped viruses at molecular level. A crucial step in this process is when the viral membrane fuses with the cell membrane. Similarly to cell–cell fusion, this step is mediated by fusion proteins (classes I–III). Several medically important viruses, notably dengue and many bunyaviruses, harbour a class II fusion protein. Class II fusion protein structures have been solved in pre- and post-fusion conformation and in some cases different factors promoting fusion have been determined. However, questions about the most important steps of this key process remain unanswered. I will focus on the entry mechanism of bunyaviruses by using cutting-edge, high spatial and temporal resolution bio-imaging techniques. These viruses have been chosen as a model system to maximise the significance of the project: they form an emerging viral threat to humans and animals, no approved vaccines or antivirals exist for human use and they are less studied than other class II fusion protein systems. Cryo-electron microscopy and tomography will be used to solve high-resolution structures (up to ~3 Å) of viruses, in addition to virus–receptor and virus–membrane complexes. Advanced fluorescence microscopy techniques will be used to probe the dynamics of virus entry and fusion in vivo and in vitro. Deciphering key steps in virus entry is expected to contribute to rational vaccine and drug design. During this project I aim to establish a world-class laboratory in structural and cellular biology of emerging viruses. The project greatly benefits from our unique biosafety level 3 laboratory offering advanced bio-imaging techniques. Furthermore it will also pave way for similar projects on other infectious viruses. Finally the novel computational image processing methods developed in this project will be broadly applicable for the analysis of flexible biological structures, which often pose the most challenging yet interesting questions in structural biology.
Summary
We aim to understand host cell entry of enveloped viruses at molecular level. A crucial step in this process is when the viral membrane fuses with the cell membrane. Similarly to cell–cell fusion, this step is mediated by fusion proteins (classes I–III). Several medically important viruses, notably dengue and many bunyaviruses, harbour a class II fusion protein. Class II fusion protein structures have been solved in pre- and post-fusion conformation and in some cases different factors promoting fusion have been determined. However, questions about the most important steps of this key process remain unanswered. I will focus on the entry mechanism of bunyaviruses by using cutting-edge, high spatial and temporal resolution bio-imaging techniques. These viruses have been chosen as a model system to maximise the significance of the project: they form an emerging viral threat to humans and animals, no approved vaccines or antivirals exist for human use and they are less studied than other class II fusion protein systems. Cryo-electron microscopy and tomography will be used to solve high-resolution structures (up to ~3 Å) of viruses, in addition to virus–receptor and virus–membrane complexes. Advanced fluorescence microscopy techniques will be used to probe the dynamics of virus entry and fusion in vivo and in vitro. Deciphering key steps in virus entry is expected to contribute to rational vaccine and drug design. During this project I aim to establish a world-class laboratory in structural and cellular biology of emerging viruses. The project greatly benefits from our unique biosafety level 3 laboratory offering advanced bio-imaging techniques. Furthermore it will also pave way for similar projects on other infectious viruses. Finally the novel computational image processing methods developed in this project will be broadly applicable for the analysis of flexible biological structures, which often pose the most challenging yet interesting questions in structural biology.
Max ERC Funding
1 998 375 €
Duration
Start date: 2015-04-01, End date: 2020-03-31
Project acronym CAVITYQPD
Project Cavity quantum phonon dynamics
Researcher (PI) Mika Antero Sillanpaeae
Host Institution (HI) AALTO KORKEAKOULUSAATIO SR
Country Finland
Call Details Consolidator Grant (CoG), PE3, ERC-2013-CoG
Summary "Large bodies usually follow the classical equations of motion. Deviations from this can be called
macroscopic quantum behavior. These phenomena have been experimentally verified with cavity Quantum
Electro Dynamics (QED), trapped ions, and superconducting Josephson junction systems. Recently, evidence
was obtained that also moving objects can display such behavior. These objects are micromechanical
resonators (MR), which can measure tens of microns in size and are hence quite macroscopic. The degree of
freedom is their vibrations: phonons.
I propose experimental research in order to push quantum mechanics closer to the classical world than ever
before. I will try find quantum behavior in the most classical objects, that is, slowly moving bodies. I will use
MR's, accessed via electrical resonators. Part of it will be in analogy to the previously studied macroscopic
systems, but with photons replaced by phonons. The experiments are done in a cryogenic temperature mostly
in dilution refrigerator. The work will open up new perspectives on how nature works, and can have
technological implications.
The first basic setup is the coupling of MR to microwave cavity resonators. This is a direct analogy to
optomechanics, and can be called circuit optomechanics. The goals will be phonon state transfer via a cavity
bus, construction of squeezed states and of phonon-cavity entanglement. The second setup is to boost the
optomechanical coupling with a Josephson junction system, and reach the single-phonon strong-coupling for
the first time. The third setup is the coupling of MR to a Josephson junction artificial atom. Here we will
access the MR same way as the motion of a trapped ions is coupled to their internal transitions. In this setup,
I am proposing to construct exotic quantum states of motion, and finally entangle and transfer phonons over
mm-distance via cavity-coupled qubits. I believe within the project it is possible to perform rudimentary Bell
measurement with phonons."
Summary
"Large bodies usually follow the classical equations of motion. Deviations from this can be called
macroscopic quantum behavior. These phenomena have been experimentally verified with cavity Quantum
Electro Dynamics (QED), trapped ions, and superconducting Josephson junction systems. Recently, evidence
was obtained that also moving objects can display such behavior. These objects are micromechanical
resonators (MR), which can measure tens of microns in size and are hence quite macroscopic. The degree of
freedom is their vibrations: phonons.
I propose experimental research in order to push quantum mechanics closer to the classical world than ever
before. I will try find quantum behavior in the most classical objects, that is, slowly moving bodies. I will use
MR's, accessed via electrical resonators. Part of it will be in analogy to the previously studied macroscopic
systems, but with photons replaced by phonons. The experiments are done in a cryogenic temperature mostly
in dilution refrigerator. The work will open up new perspectives on how nature works, and can have
technological implications.
The first basic setup is the coupling of MR to microwave cavity resonators. This is a direct analogy to
optomechanics, and can be called circuit optomechanics. The goals will be phonon state transfer via a cavity
bus, construction of squeezed states and of phonon-cavity entanglement. The second setup is to boost the
optomechanical coupling with a Josephson junction system, and reach the single-phonon strong-coupling for
the first time. The third setup is the coupling of MR to a Josephson junction artificial atom. Here we will
access the MR same way as the motion of a trapped ions is coupled to their internal transitions. In this setup,
I am proposing to construct exotic quantum states of motion, and finally entangle and transfer phonons over
mm-distance via cavity-coupled qubits. I believe within the project it is possible to perform rudimentary Bell
measurement with phonons."
Max ERC Funding
2 004 283 €
Duration
Start date: 2015-01-01, End date: 2019-12-31
Project acronym CELLFITNESS
Project Active Mechanisms of Cell Selection: From Cell Competition to Cell Fitness
Researcher (PI) Eduardo Moreno Lampaya
Host Institution (HI) FUNDACAO D. ANNA SOMMER CHAMPALIMAUD E DR. CARLOS MONTEZ CHAMPALIMAUD
Country Portugal
Call Details Consolidator Grant (CoG), LS3, ERC-2013-CoG
Summary The molecular mechanisms that mediate cell competition, cell fitness and cell selection is gaining interest. With innovative approaches, molecules and ground-breaking hypothesis, this field of research can help understand several biological processes such as development, cancer and tissue degeneration. The project has 3 clear and ambitious objectives: 1. We propose to identify all the key genes mediating cell competition and their molecular mechanisms. In order to reach this objective we will use data from two whole genome screens in Drosophila where we have identified 7 key genes. By the end of this CoG grant, we should have no big gaps in our knowledge of how slow dividing cells are recognised and eliminated in Drosophila. 2. In addition, we will explore how general the cell competition pathways are and how they can impact biomedical research, with a focus in cancer and tissue degeneration. The interest in cancer is based on experiments in Drosophila and mice where we and others have found that an active process of cell selection determines tumour growth. Preliminary results suggest that the pathways identified do not only play important roles in the elimination of slow dividing cells, but also during cancer initiation and progression. 3. We will further explore the role of cell competition in neuronal selection, specially during neurodegeneration, development of the retina and adult brain regeneration in Drosophila. This proposal is of an interdisciplinary nature because it takes a basic cellular mechanism (the genetic pathways that select cells within tissues) and crosses boundaries between different fields of research: development, cancer, regeneration and tissue degeneration. In this ERC CoG proposal, we are committed to continue our efforts from basic science to biomedical approaches. The phenomena of cell competition and its participating genes have the potential to discover novel biomarkers and therapeutic strategies against cancer and tissue degeneration.
Summary
The molecular mechanisms that mediate cell competition, cell fitness and cell selection is gaining interest. With innovative approaches, molecules and ground-breaking hypothesis, this field of research can help understand several biological processes such as development, cancer and tissue degeneration. The project has 3 clear and ambitious objectives: 1. We propose to identify all the key genes mediating cell competition and their molecular mechanisms. In order to reach this objective we will use data from two whole genome screens in Drosophila where we have identified 7 key genes. By the end of this CoG grant, we should have no big gaps in our knowledge of how slow dividing cells are recognised and eliminated in Drosophila. 2. In addition, we will explore how general the cell competition pathways are and how they can impact biomedical research, with a focus in cancer and tissue degeneration. The interest in cancer is based on experiments in Drosophila and mice where we and others have found that an active process of cell selection determines tumour growth. Preliminary results suggest that the pathways identified do not only play important roles in the elimination of slow dividing cells, but also during cancer initiation and progression. 3. We will further explore the role of cell competition in neuronal selection, specially during neurodegeneration, development of the retina and adult brain regeneration in Drosophila. This proposal is of an interdisciplinary nature because it takes a basic cellular mechanism (the genetic pathways that select cells within tissues) and crosses boundaries between different fields of research: development, cancer, regeneration and tissue degeneration. In this ERC CoG proposal, we are committed to continue our efforts from basic science to biomedical approaches. The phenomena of cell competition and its participating genes have the potential to discover novel biomarkers and therapeutic strategies against cancer and tissue degeneration.
Max ERC Funding
1 968 062 €
Duration
Start date: 2014-06-01, End date: 2019-05-31
Project acronym CentrioleBirthDeath
Project Mechanism of centriole inheritance and maintenance
Researcher (PI) Monica BETTENCOURT CARVALHO DIAS
Host Institution (HI) FUNDACAO CALOUSTE GULBENKIAN
Country Portugal
Call Details Consolidator Grant (CoG), LS3, ERC-2015-CoG
Summary Centrioles assemble centrosomes and cilia/flagella, critical structures for cell division, polarity, motility and signalling, which are often deregulated in human disease. Centriole inheritance, in particular the preservation of their copy number and position in the cell is critical in many eukaryotes. I propose to investigate, in an integrative and quantitative way, how centrioles are formed in the right numbers at the right time and place, and how they are maintained to ensure their function and inheritance. We first ask how centrioles guide their own assembly position and centriole copy number. Our recent work highlighted several properties of the system, including positive and negative feedbacks and spatial cues. We explore critical hypotheses through a combination of biochemistry, quantitative live cell microscopy and computational modelling. We then ask how the centrosome and the cell cycle are both coordinated. We recently identified the triggering event in centriole biogenesis and how its regulation is akin to cell cycle control of DNA replication and centromere assembly. We will explore new hypotheses to understand how assembly time is coupled to the cell cycle. Lastly, we ask how centriole maintenance is regulated. By studying centriole disappearance in the female germline we uncovered that centrioles need to be actively maintained by their surrounding matrix. We propose to investigate how that matrix provides stability to the centrioles, whether this is differently regulated in different cell types and the possible consequences of its misregulation for the organism (infertility and ciliopathy-like symptoms). We will take advantage of several experimental systems (in silico, ex-vivo, flies and human cells), tailoring the assay to the question and allowing for comparisons across experimental systems to provide a deeper understanding of the process and its regulation.
Summary
Centrioles assemble centrosomes and cilia/flagella, critical structures for cell division, polarity, motility and signalling, which are often deregulated in human disease. Centriole inheritance, in particular the preservation of their copy number and position in the cell is critical in many eukaryotes. I propose to investigate, in an integrative and quantitative way, how centrioles are formed in the right numbers at the right time and place, and how they are maintained to ensure their function and inheritance. We first ask how centrioles guide their own assembly position and centriole copy number. Our recent work highlighted several properties of the system, including positive and negative feedbacks and spatial cues. We explore critical hypotheses through a combination of biochemistry, quantitative live cell microscopy and computational modelling. We then ask how the centrosome and the cell cycle are both coordinated. We recently identified the triggering event in centriole biogenesis and how its regulation is akin to cell cycle control of DNA replication and centromere assembly. We will explore new hypotheses to understand how assembly time is coupled to the cell cycle. Lastly, we ask how centriole maintenance is regulated. By studying centriole disappearance in the female germline we uncovered that centrioles need to be actively maintained by their surrounding matrix. We propose to investigate how that matrix provides stability to the centrioles, whether this is differently regulated in different cell types and the possible consequences of its misregulation for the organism (infertility and ciliopathy-like symptoms). We will take advantage of several experimental systems (in silico, ex-vivo, flies and human cells), tailoring the assay to the question and allowing for comparisons across experimental systems to provide a deeper understanding of the process and its regulation.
Max ERC Funding
2 000 000 €
Duration
Start date: 2017-01-01, End date: 2021-12-31
Project acronym ChronosAntibiotics
Project Exploring the bacterial cell cycle to re-sensitize antibiotic-resistant bacteria
Researcher (PI) MARIANA LUISA TOMAS GOMES DE PINHO
Host Institution (HI) UNIVERSIDADE NOVA DE LISBOA
Country Portugal
Call Details Consolidator Grant (CoG), LS6, ERC-2017-COG
Summary Over the next 35 years, antibiotic resistant bacteria are expected to kill more than 300 million people. The need to find alternative strategies for antimicrobial therapies remains a global challenge with several bottlenecks in the antibiotic discovery process. Using Staphylococcus aureus, the most common multidrug-resistant bacterium in the European Union and an excellent model organism for cell division in cocci, we propose:
(i) to find new pathways to re-sensitize resistant bacteria. Bacteria undergo major morphology changes during the cell cycle. We hypothesize that these changes generate windows of opportunity during which bacteria are more susceptible or more tolerant to the action of antibiotics. We will identify key regulators of the cell cycle in order to manipulate the duration of windows of opportunity for the action of existing antibiotics.
(ii) to develop new fluorescence-based reporters for whole-cell screenings of antimicrobial compounds with new modes of action, including compounds that arrest or delay the cell cycle; compounds that target non-essential pathways that are required for expression of resistance against existing antibiotics and therefore can be used as synergistic drugs for combination therapies; compounds that inhibit the production of virulence factors and compounds that revert persister states that are phenotypically resistant to antibiotics.
(iii) to unravel new modes of action of antibiotics by using the constructed reporter strains as powerful tools to learn how antibiotics act at the single cell level.
Over the past years, my group has become expert on the biology of S. aureus, has constructed powerful biological tools to study cell division and synthesis of the cell surface and has studied mechanisms of action of various antimicrobial compounds. We are therefore in a privileged position to quickly unravel the function of new players in the bacterial cell cycle and simultaneously contribute to accelerate antibiotic discovery.
Summary
Over the next 35 years, antibiotic resistant bacteria are expected to kill more than 300 million people. The need to find alternative strategies for antimicrobial therapies remains a global challenge with several bottlenecks in the antibiotic discovery process. Using Staphylococcus aureus, the most common multidrug-resistant bacterium in the European Union and an excellent model organism for cell division in cocci, we propose:
(i) to find new pathways to re-sensitize resistant bacteria. Bacteria undergo major morphology changes during the cell cycle. We hypothesize that these changes generate windows of opportunity during which bacteria are more susceptible or more tolerant to the action of antibiotics. We will identify key regulators of the cell cycle in order to manipulate the duration of windows of opportunity for the action of existing antibiotics.
(ii) to develop new fluorescence-based reporters for whole-cell screenings of antimicrobial compounds with new modes of action, including compounds that arrest or delay the cell cycle; compounds that target non-essential pathways that are required for expression of resistance against existing antibiotics and therefore can be used as synergistic drugs for combination therapies; compounds that inhibit the production of virulence factors and compounds that revert persister states that are phenotypically resistant to antibiotics.
(iii) to unravel new modes of action of antibiotics by using the constructed reporter strains as powerful tools to learn how antibiotics act at the single cell level.
Over the past years, my group has become expert on the biology of S. aureus, has constructed powerful biological tools to study cell division and synthesis of the cell surface and has studied mechanisms of action of various antimicrobial compounds. We are therefore in a privileged position to quickly unravel the function of new players in the bacterial cell cycle and simultaneously contribute to accelerate antibiotic discovery.
Max ERC Funding
2 533 500 €
Duration
Start date: 2018-03-01, End date: 2023-02-28
Project acronym CODECHECK
Project CRACKING THE CODE BEHIND MITOTIC FIDELITY: the roles of tubulin post-translational modifications and a chromosome separation checkpoint
Researcher (PI) Helder Jose Martins Maiato
Host Institution (HI) INSTITUTO DE BIOLOGIA MOLECULAR E CELULAR-IBMC
Country Portugal
Call Details Consolidator Grant (CoG), LS3, ERC-2015-CoG
Summary During the human lifetime 10000 trillion cell divisions take place to ensure tissue homeostasis and several vital functions in the organism. Mitosis is the process that ensures that dividing cells preserve the chromosome number of their progenitors, while deviation from this, a condition known as aneuploidy, represents the most common feature in human cancers. Here we will test two original concepts with strong implications for chromosome segregation fidelity. The first concept is based on the “tubulin code” hypothesis, which predicts that molecular motors “read” tubulin post-translational modifications on spindle microtubules. Our proof-of-concept experiments demonstrate that tubulin detyrosination works as a navigation system that guides chromosomes towards the cell equator. Thus, in addition to regulating the motors required for chromosome motion, the cell might regulate the tracks in which they move on. We will combine proteomic, super-resolution and live-cell microscopy, with in vitro reconstitutions, to perform a comprehensive survey of the tubulin code and the respective implications for motors involved in chromosome motion, mitotic spindle assembly and correction of kinetochore-microtubule attachments. The second concept is centered on the recently uncovered chromosome separation checkpoint mediated by a midzone-associated Aurora B gradient, which delays nuclear envelope reformation in response to incompletely separated chromosomes. We aim to identify Aurora B targets involved in the spatiotemporal regulation of the anaphase-telophase transition. We will establish powerful live-cell microscopy assays and a novel mammalian model system to dissect how this checkpoint allows the detection and correction of lagging/long chromosomes and DNA bridges that would otherwise contribute to genomic instability. Overall, this work will establish a paradigm shift in our understanding of how spatial information is conveyed to faithfully segregate chromosomes during mitosis.
Summary
During the human lifetime 10000 trillion cell divisions take place to ensure tissue homeostasis and several vital functions in the organism. Mitosis is the process that ensures that dividing cells preserve the chromosome number of their progenitors, while deviation from this, a condition known as aneuploidy, represents the most common feature in human cancers. Here we will test two original concepts with strong implications for chromosome segregation fidelity. The first concept is based on the “tubulin code” hypothesis, which predicts that molecular motors “read” tubulin post-translational modifications on spindle microtubules. Our proof-of-concept experiments demonstrate that tubulin detyrosination works as a navigation system that guides chromosomes towards the cell equator. Thus, in addition to regulating the motors required for chromosome motion, the cell might regulate the tracks in which they move on. We will combine proteomic, super-resolution and live-cell microscopy, with in vitro reconstitutions, to perform a comprehensive survey of the tubulin code and the respective implications for motors involved in chromosome motion, mitotic spindle assembly and correction of kinetochore-microtubule attachments. The second concept is centered on the recently uncovered chromosome separation checkpoint mediated by a midzone-associated Aurora B gradient, which delays nuclear envelope reformation in response to incompletely separated chromosomes. We aim to identify Aurora B targets involved in the spatiotemporal regulation of the anaphase-telophase transition. We will establish powerful live-cell microscopy assays and a novel mammalian model system to dissect how this checkpoint allows the detection and correction of lagging/long chromosomes and DNA bridges that would otherwise contribute to genomic instability. Overall, this work will establish a paradigm shift in our understanding of how spatial information is conveyed to faithfully segregate chromosomes during mitosis.
Max ERC Funding
2 323 468 €
Duration
Start date: 2016-07-01, End date: 2021-06-30
