Project acronym ACAP
Project Acency Costs and Asset Pricing
Researcher (PI) Thomas Mariotti
Host Institution (HI) FONDATION JEAN JACQUES LAFFONT,TOULOUSE SCIENCES ECONOMIQUES
Country France
Call Details Starting Grant (StG), SH1, ERC-2007-StG
Summary The main objective of this research project is to contribute at bridging the gap between the two main branches of financial theory, namely corporate finance and asset pricing. It is motivated by the conviction that these two aspects of financial activity should and can be analyzed within a unified framework. This research will borrow from these two approaches in order to construct theoretical models that allow one to analyze the design and issuance of financial securities, as well as the dynamics of their valuations. Unlike asset pricing, which takes as given the price of the fundamentals, the goal is to derive security price processes from a precise description of firm’s operations and internal frictions. Regarding the latter, and in line with traditional corporate finance theory, the analysis will emphasize the role of agency costs within the firm for the design of its securities. But the analysis will be pushed one step further by studying the impact of these agency costs on key financial variables such as stock and bond prices, leverage, book-to-market ratios, default risk, or the holding of liquidities by firms. One of the contributions of this research project is to show how these variables are interrelated when firms and investors agree upon optimal financial arrangements. The final objective is to derive a rich set of testable asset pricing implications that would eventually be brought to the data.
Summary
The main objective of this research project is to contribute at bridging the gap between the two main branches of financial theory, namely corporate finance and asset pricing. It is motivated by the conviction that these two aspects of financial activity should and can be analyzed within a unified framework. This research will borrow from these two approaches in order to construct theoretical models that allow one to analyze the design and issuance of financial securities, as well as the dynamics of their valuations. Unlike asset pricing, which takes as given the price of the fundamentals, the goal is to derive security price processes from a precise description of firm’s operations and internal frictions. Regarding the latter, and in line with traditional corporate finance theory, the analysis will emphasize the role of agency costs within the firm for the design of its securities. But the analysis will be pushed one step further by studying the impact of these agency costs on key financial variables such as stock and bond prices, leverage, book-to-market ratios, default risk, or the holding of liquidities by firms. One of the contributions of this research project is to show how these variables are interrelated when firms and investors agree upon optimal financial arrangements. The final objective is to derive a rich set of testable asset pricing implications that would eventually be brought to the data.
Max ERC Funding
1 000 000 €
Duration
Start date: 2008-11-01, End date: 2014-10-31
Project acronym aLzINK
Project Alzheimer's disease and Zinc: the missing link ?
Researcher (PI) Christelle Sandrine Florence HUREAU-SABATER
Host Institution (HI) CENTRE NATIONAL DE LA RECHERCHE SCIENTIFIQUE CNRS
Country France
Call Details Starting Grant (StG), PE5, ERC-2014-STG
Summary Alzheimer's disease (AD) is one of the most serious diseases mankind is now facing as its social and economical impacts are increasing fastly. AD is very complex and the amyloid-β (Aβ) peptide as well as metallic ions (mainly copper and zinc) have been linked to its aetiology. While the deleterious impact of Cu is widely acknowledged, intervention of Zn is certain but still needs to be figured out.
The main objective of the present proposal, which is strongly anchored in the bio-inorganic chemistry field at interface with spectroscopy and biochemistry, is to design, synthesize and study new drug candidates (ligands L) capable of (i) targeting Cu(II) bound to Aβ within the synaptic cleft, where Zn is co-localized and ultimately to develop Zn-driven Cu(II) removal from Aβ and (ii) disrupting the aberrant Cu(II)-Aβ interactions involved in ROS production and Aβ aggregation, two deleterious events in AD. The drug candidates will thus have high Cu(II) over Zn selectively to preserve the crucial physiological role of Zn in the neurotransmission process. Zn is always underestimated (if not completely neglected) in current therapeutic approaches targeting Cu(II) despite the known interference of Zn with Cu(II) binding.
To reach this objective, it is absolutely necessary to first understand the metal ions trafficking issues in presence of Aβ alone at a molecular level (i.e. without the drug candidates).This includes: (i) determination of Zn binding site to Aβ, impact on Aβ aggregation and cell toxicity, (ii) determination of the mutual influence of Zn and Cu to their coordination to Aβ, impact on Aβ aggregation, ROS production and cell toxicity.
Methods used will span from organic synthesis to studies of neuronal model cells, with a major contribution of a wide panel of spectroscopic techniques including NMR, EPR, mass spectrometry, fluorescence, UV-Vis, circular-dichroism, X-ray absorption spectroscopy...
Summary
Alzheimer's disease (AD) is one of the most serious diseases mankind is now facing as its social and economical impacts are increasing fastly. AD is very complex and the amyloid-β (Aβ) peptide as well as metallic ions (mainly copper and zinc) have been linked to its aetiology. While the deleterious impact of Cu is widely acknowledged, intervention of Zn is certain but still needs to be figured out.
The main objective of the present proposal, which is strongly anchored in the bio-inorganic chemistry field at interface with spectroscopy and biochemistry, is to design, synthesize and study new drug candidates (ligands L) capable of (i) targeting Cu(II) bound to Aβ within the synaptic cleft, where Zn is co-localized and ultimately to develop Zn-driven Cu(II) removal from Aβ and (ii) disrupting the aberrant Cu(II)-Aβ interactions involved in ROS production and Aβ aggregation, two deleterious events in AD. The drug candidates will thus have high Cu(II) over Zn selectively to preserve the crucial physiological role of Zn in the neurotransmission process. Zn is always underestimated (if not completely neglected) in current therapeutic approaches targeting Cu(II) despite the known interference of Zn with Cu(II) binding.
To reach this objective, it is absolutely necessary to first understand the metal ions trafficking issues in presence of Aβ alone at a molecular level (i.e. without the drug candidates).This includes: (i) determination of Zn binding site to Aβ, impact on Aβ aggregation and cell toxicity, (ii) determination of the mutual influence of Zn and Cu to their coordination to Aβ, impact on Aβ aggregation, ROS production and cell toxicity.
Methods used will span from organic synthesis to studies of neuronal model cells, with a major contribution of a wide panel of spectroscopic techniques including NMR, EPR, mass spectrometry, fluorescence, UV-Vis, circular-dichroism, X-ray absorption spectroscopy...
Max ERC Funding
1 499 948 €
Duration
Start date: 2015-03-01, End date: 2021-08-31
Project acronym ATMOFLEX
Project Turbulent Transport in the Atmosphere: Fluctuations and Extreme Events
Researcher (PI) Jeremie Bec
Host Institution (HI) CENTRE NATIONAL DE LA RECHERCHE SCIENTIFIQUE CNRS
Country France
Call Details Starting Grant (StG), PE3, ERC-2009-StG
Summary A major part of the physical and chemical processes occurring in the atmosphere involves the turbulent transport of tiny particles. Current studies and models use a formulation in terms of mean fields, where the strong variations in the dynamical and statistical properties of the particles are neglected and where the underlying fluctuations of the fluid flow velocity are oversimplified. Devising an accurate understanding of the influence of air turbulence and of the extreme fluctuations that it generates in the dispersed phase remains a challenging issue. This project aims at coordinating and integrating theoretical, numerical, experimental, and observational efforts to develop a new statistical understanding of the role of fluctuations in atmospheric transport processes. The proposed work will cover individual as well as collective behaviors and will provide a systematic and unified description of targeted specific processes involving suspended drops or particles: the dispersion of pollutants from a source, the growth by condensation and coagulation of droplets and ice crystals in clouds, the scavenging, settling and re-suspension of aerosols, and the radiative and climatic effects of particles. The proposed approach is based on the use of tools borrowed from statistical physics and field theory, and from the theory of large deviations and of random dynamical systems in order to design new observables that will be simultaneously tractable analytically in simplified models and of relevance for the quantitative handling of such physical mechanisms. One of the outcomes will be to provide a new framework for improving and refining the methods used in meteorology and atmospheric sciences and to answer the long-standing question of the effects of suspended particles onto climate.
Summary
A major part of the physical and chemical processes occurring in the atmosphere involves the turbulent transport of tiny particles. Current studies and models use a formulation in terms of mean fields, where the strong variations in the dynamical and statistical properties of the particles are neglected and where the underlying fluctuations of the fluid flow velocity are oversimplified. Devising an accurate understanding of the influence of air turbulence and of the extreme fluctuations that it generates in the dispersed phase remains a challenging issue. This project aims at coordinating and integrating theoretical, numerical, experimental, and observational efforts to develop a new statistical understanding of the role of fluctuations in atmospheric transport processes. The proposed work will cover individual as well as collective behaviors and will provide a systematic and unified description of targeted specific processes involving suspended drops or particles: the dispersion of pollutants from a source, the growth by condensation and coagulation of droplets and ice crystals in clouds, the scavenging, settling and re-suspension of aerosols, and the radiative and climatic effects of particles. The proposed approach is based on the use of tools borrowed from statistical physics and field theory, and from the theory of large deviations and of random dynamical systems in order to design new observables that will be simultaneously tractable analytically in simplified models and of relevance for the quantitative handling of such physical mechanisms. One of the outcomes will be to provide a new framework for improving and refining the methods used in meteorology and atmospheric sciences and to answer the long-standing question of the effects of suspended particles onto climate.
Max ERC Funding
1 200 000 €
Duration
Start date: 2009-11-01, End date: 2014-10-31
Project acronym Autophagy in vitro
Project Reconstituting Autophagosome Biogenesis in vitro
Researcher (PI) Thomas Wollert
Host Institution (HI) INSTITUT PASTEUR
Country France
Call Details Starting Grant (StG), LS1, ERC-2014-STG
Summary Autophagy is a catabolic pathway that delivers cytoplasmic material to lysosomes for degradation. Under vegetative conditions, the pathway serves as quality control system, specifically targeting damaged or superfluous organelles and protein-aggregates. Cytotoxic stresses and starvation, however, induces the formation of larger autophagosomes that capture cargo unselectively. Autophagosomes are being generated from a cup-shaped precursor membrane, the isolation membrane, which expands to engulf cytoplasmic components. Sealing of this structure gives rise to the double-membrane surrounded autophagosomes. Two interconnected ubiquitin (Ub)-like conjugation systems coordinate the expansion of autophagosomes by conjugating the autophagy related (Atg)-protein Atg8 to the isolation membrane. In an effort to unravel the function of Atg8, we reconstituted the system on model membranes in vitro and found that Atg8 forms together with the Atg12–Atg5-Atg16 complex a membrane scaffold which is required for productive autophagy in yeast. Humans possess seven Atg8-homologs and two mutually exclusive Atg16-variants. Here, we propose to investigate the function of the human Ub-like conjugation system using a fully reconstituted in vitro system. The spatiotemporal organization of recombinant fluorescent-labeled proteins with synthetic model membranes will be investigated using confocal and TIRF-microscopy. Structural information will be obtained by atomic force and electron microscopy. Mechanistic insights, obtained from the in vitro work, will be tested in vivo in cultured human cells. We belief that revealing 1) the function of the human Ub-like conjugation system in autophagy, 2) the functional differences of Atg8-homologs and the two Atg16-variants Atg16L1 and TECPR1 and 3) how Atg16L1 coordinates non-canonical autophagy will provide essential insights into the pathophysiology of cancer, neurodegenerative, and autoimmune diseases.
Summary
Autophagy is a catabolic pathway that delivers cytoplasmic material to lysosomes for degradation. Under vegetative conditions, the pathway serves as quality control system, specifically targeting damaged or superfluous organelles and protein-aggregates. Cytotoxic stresses and starvation, however, induces the formation of larger autophagosomes that capture cargo unselectively. Autophagosomes are being generated from a cup-shaped precursor membrane, the isolation membrane, which expands to engulf cytoplasmic components. Sealing of this structure gives rise to the double-membrane surrounded autophagosomes. Two interconnected ubiquitin (Ub)-like conjugation systems coordinate the expansion of autophagosomes by conjugating the autophagy related (Atg)-protein Atg8 to the isolation membrane. In an effort to unravel the function of Atg8, we reconstituted the system on model membranes in vitro and found that Atg8 forms together with the Atg12–Atg5-Atg16 complex a membrane scaffold which is required for productive autophagy in yeast. Humans possess seven Atg8-homologs and two mutually exclusive Atg16-variants. Here, we propose to investigate the function of the human Ub-like conjugation system using a fully reconstituted in vitro system. The spatiotemporal organization of recombinant fluorescent-labeled proteins with synthetic model membranes will be investigated using confocal and TIRF-microscopy. Structural information will be obtained by atomic force and electron microscopy. Mechanistic insights, obtained from the in vitro work, will be tested in vivo in cultured human cells. We belief that revealing 1) the function of the human Ub-like conjugation system in autophagy, 2) the functional differences of Atg8-homologs and the two Atg16-variants Atg16L1 and TECPR1 and 3) how Atg16L1 coordinates non-canonical autophagy will provide essential insights into the pathophysiology of cancer, neurodegenerative, and autoimmune diseases.
Max ERC Funding
1 499 726 €
Duration
Start date: 2015-04-01, End date: 2021-01-31
Project acronym BetaRegeneration
Project Induction of Insulin-producing beta-cells Regeneration in vivo
Researcher (PI) Patrick Collombat
Host Institution (HI) INSTITUT NATIONAL DE LA SANTE ET DE LA RECHERCHE MEDICALE
Country France
Call Details Starting Grant (StG), LS4, ERC-2011-StG_20101109
Summary Diabetes has become one of the most widespread metabolic disorders with epidemic dimensions affecting almost 6% of the world’s population. Despite modern treatments, the life expectancy of patients with Type 1 diabetes remains reduced as compared to healthy subjects. There is therefore a need for alternative therapies. Towards this aim, using the mouse, we recently demonstrated that the in vivo forced expression of a single factor in pancreatic alpha-cells is sufficient to induce a continuous regeneration of alpha-cells and their subsequent conversion into beta-like cells, such converted cells being capable of reversing the consequences of chemically-induced diabetes in vivo (Collombat et al. Cell, 2009).
The PI and his team therefore propose to further decipher the mechanisms involved in this alpha-cell-mediated beta-cell regeneration process and determine whether this approach may be applied to adult animals and whether it would efficiently reverse Type 1 diabetes. Furthermore, a major effort will be made to verify whether our findings could be translated to human. Specifically, we will use a tri-partite approach to address the following issues: (1) Can the in vivo alpha-cell-mediated beta-cell regeneration be induced in adults mice? What would be the genetic determinants involved? (2) Can alpha-cell-mediated beta-cell regeneration reverse diabetes in the NOD Type 1 diabetes mouse model? (3) Can adult human alpha-cells be converted into beta-like cells?
Together, these ambitious objectives will most certainly allow us to gain new insight into the mechanisms defining the identity and the reprogramming capabilities of mouse and human endocrine cells and may thereby open new avenues for the treatment of diabetes. Similarly, the determination of the molecular triggers implicated in the beta-cell regeneration observed in our diabetic mice may lead to exciting new findings, including the identification of “drugable” targets of importance for human diabetic patients.
Summary
Diabetes has become one of the most widespread metabolic disorders with epidemic dimensions affecting almost 6% of the world’s population. Despite modern treatments, the life expectancy of patients with Type 1 diabetes remains reduced as compared to healthy subjects. There is therefore a need for alternative therapies. Towards this aim, using the mouse, we recently demonstrated that the in vivo forced expression of a single factor in pancreatic alpha-cells is sufficient to induce a continuous regeneration of alpha-cells and their subsequent conversion into beta-like cells, such converted cells being capable of reversing the consequences of chemically-induced diabetes in vivo (Collombat et al. Cell, 2009).
The PI and his team therefore propose to further decipher the mechanisms involved in this alpha-cell-mediated beta-cell regeneration process and determine whether this approach may be applied to adult animals and whether it would efficiently reverse Type 1 diabetes. Furthermore, a major effort will be made to verify whether our findings could be translated to human. Specifically, we will use a tri-partite approach to address the following issues: (1) Can the in vivo alpha-cell-mediated beta-cell regeneration be induced in adults mice? What would be the genetic determinants involved? (2) Can alpha-cell-mediated beta-cell regeneration reverse diabetes in the NOD Type 1 diabetes mouse model? (3) Can adult human alpha-cells be converted into beta-like cells?
Together, these ambitious objectives will most certainly allow us to gain new insight into the mechanisms defining the identity and the reprogramming capabilities of mouse and human endocrine cells and may thereby open new avenues for the treatment of diabetes. Similarly, the determination of the molecular triggers implicated in the beta-cell regeneration observed in our diabetic mice may lead to exciting new findings, including the identification of “drugable” targets of importance for human diabetic patients.
Max ERC Funding
1 500 000 €
Duration
Start date: 2012-01-01, End date: 2016-12-31
Project acronym BioMatrix
Project Structural Biology of Exopolysaccharide Secretion in Bacterial Biofilms
Researcher (PI) Petya Violinova KRASTEVA
Host Institution (HI) CENTRE NATIONAL DE LA RECHERCHE SCIENTIFIQUE CNRS
Country France
Call Details Starting Grant (StG), LS1, ERC-2017-STG
Summary Bacterial biofilm formation is a paramount developmental process in both Gram-positive and Gram-negative species and in many pathogens has been associated with processes of horizontal gene transfer, antibiotic resistance development and pathogen persistence. Bacterial biofilms are collaborative sessile macrocolonies embedded in complex extracellular matrix that secures both mechanical resistance and a medium for intercellular exchange.
Biogenesis platforms for the secretion of biofilm matrix components - many of which controlled directly or indirectly by the intracellular second messenger c-di-GMP - are important determinants for biofilm formation and bacterial disease, and therefore present compelling targets for the development of novel therapeutics. During my Ph.D. and post-doctoral work I studied the structure and function of c-di-GMP-sensing protein factors controling extracellular matrix production by DNA-binding at the transcription initiation level or by inside-out signalling mechanisms at the cell envelope, as well as membrane exporters involved directly in downstream matrix component secretion.
Here, I propose to apply my expertise in microbiology, protein science and structural biology to study the structure and function of exopolysaccharide secretion systems in Gram-negative species. Using Pseudomonas aeruginosa, Vibrio spp. and Escherichia coli as model organisms, my team will aim to reveal the global architecture and individual building components of several expolysaccharide-producing protein megacomplexes. We will combine X-ray crystallography, biophysical and biochemical assays, electron microscopy and in cellulo functional studies to provide a comprehensive view of extracellular matrix production that spans the different resolution levels and presents molecular blueprints for the development of novel anti-infectives. Over the last year I have laid the foundation of these studies and have demonstrated the overall feasibility of the project.
Summary
Bacterial biofilm formation is a paramount developmental process in both Gram-positive and Gram-negative species and in many pathogens has been associated with processes of horizontal gene transfer, antibiotic resistance development and pathogen persistence. Bacterial biofilms are collaborative sessile macrocolonies embedded in complex extracellular matrix that secures both mechanical resistance and a medium for intercellular exchange.
Biogenesis platforms for the secretion of biofilm matrix components - many of which controlled directly or indirectly by the intracellular second messenger c-di-GMP - are important determinants for biofilm formation and bacterial disease, and therefore present compelling targets for the development of novel therapeutics. During my Ph.D. and post-doctoral work I studied the structure and function of c-di-GMP-sensing protein factors controling extracellular matrix production by DNA-binding at the transcription initiation level or by inside-out signalling mechanisms at the cell envelope, as well as membrane exporters involved directly in downstream matrix component secretion.
Here, I propose to apply my expertise in microbiology, protein science and structural biology to study the structure and function of exopolysaccharide secretion systems in Gram-negative species. Using Pseudomonas aeruginosa, Vibrio spp. and Escherichia coli as model organisms, my team will aim to reveal the global architecture and individual building components of several expolysaccharide-producing protein megacomplexes. We will combine X-ray crystallography, biophysical and biochemical assays, electron microscopy and in cellulo functional studies to provide a comprehensive view of extracellular matrix production that spans the different resolution levels and presents molecular blueprints for the development of novel anti-infectives. Over the last year I have laid the foundation of these studies and have demonstrated the overall feasibility of the project.
Max ERC Funding
1 499 901 €
Duration
Start date: 2018-08-01, End date: 2023-07-31
Project acronym BIOMIM
Project Biomimetic films and membranes as advanced materials for studies on cellular processes
Researcher (PI) Catherine Cecile Picart
Host Institution (HI) INSTITUT POLYTECHNIQUE DE GRENOBLE
Country France
Call Details Starting Grant (StG), PE5, ERC-2010-StG_20091028
Summary The main objective nowadays in the field of biomaterials is to design highly performing bioinspired materials learning from natural processes. Importantly, biochemical and physical cues are key parameters that can affect cellular processes. Controlling processes that occur at the cell/material interface is also of prime importance to guide the cell response. The main aim of the current project is to develop novel functional bio-nanomaterials for in vitro biological studies. Our strategy is based on two related projects.
The first project deals with the rational design of smart films with foreseen applications in musculoskeletal tissue engineering. We will gain knowledge of key cellular processes by designing well defined self-assembled thin coatings. These multi-functional surfaces with bioactivity (incorporation of growth factors), mechanical (film stiffness) and topographical properties (spatial control of the film s properties) will serve as tools to mimic the complexity of the natural materials in vivo and to present bioactive molecules in the solid phase. We will get a better fundamental understanding of how cellular functions, including adhesion and differentiation of muscle cells are affected by the materials s surface properties.
In the second project, we will investigate at the molecular level a crucial aspect of cell adhesion and motility, which is the intracellular linkage between the plasma membrane and the cell cytoskeleton. We aim to elucidate the role of ERM proteins, especially ezrin and moesin, in the direct linkage between the plasma membrane and actin filaments. Here again, we will use a well defined microenvironment in vitro to simplify the complexity of the interactions that occur in cellulo. To this end, lipid membranes containing a key regulator lipid from the phosphoinositides familly, PIP2, will be employed in conjunction with purified proteins to investigate actin regulation by ERM proteins in the presence of PIP2-membranes.
Summary
The main objective nowadays in the field of biomaterials is to design highly performing bioinspired materials learning from natural processes. Importantly, biochemical and physical cues are key parameters that can affect cellular processes. Controlling processes that occur at the cell/material interface is also of prime importance to guide the cell response. The main aim of the current project is to develop novel functional bio-nanomaterials for in vitro biological studies. Our strategy is based on two related projects.
The first project deals with the rational design of smart films with foreseen applications in musculoskeletal tissue engineering. We will gain knowledge of key cellular processes by designing well defined self-assembled thin coatings. These multi-functional surfaces with bioactivity (incorporation of growth factors), mechanical (film stiffness) and topographical properties (spatial control of the film s properties) will serve as tools to mimic the complexity of the natural materials in vivo and to present bioactive molecules in the solid phase. We will get a better fundamental understanding of how cellular functions, including adhesion and differentiation of muscle cells are affected by the materials s surface properties.
In the second project, we will investigate at the molecular level a crucial aspect of cell adhesion and motility, which is the intracellular linkage between the plasma membrane and the cell cytoskeleton. We aim to elucidate the role of ERM proteins, especially ezrin and moesin, in the direct linkage between the plasma membrane and actin filaments. Here again, we will use a well defined microenvironment in vitro to simplify the complexity of the interactions that occur in cellulo. To this end, lipid membranes containing a key regulator lipid from the phosphoinositides familly, PIP2, will be employed in conjunction with purified proteins to investigate actin regulation by ERM proteins in the presence of PIP2-membranes.
Max ERC Funding
1 499 996 €
Duration
Start date: 2011-06-01, End date: 2016-05-31
Project acronym BioPoweredCL
Project Bright and biologically powered chemiluminescent labels for cell and tissue imaging
Researcher (PI) Alessandro ALIPRANDI
Host Institution (HI) CENTRE NATIONAL DE LA RECHERCHE SCIENTIFIQUE CNRS
Country France
Call Details Starting Grant (StG), PE5, ERC-2020-STG
Summary Imaging is one of the most powerful technique to visualize molecules, tissues, to understand and follow processes and it is the most used diagnostic tool in vitro and in vivo, Current biomedical imaging techniques can have high sensitivity, good spatial/temporal resolution and, in some cases, high tissue penetration but cannot combine all of these desired properties without using harmful radiations (or toxic labels) or very expensive equipment. Optical imaging techniques represent the best compromise among them; however, their ability to scale to human body is precluded. The main restriction of fluorescence imaging is that it requires light excitation which is limited by tissue absorption and scattering. Such limitations are not present in chemiluminescence imaging since light production occurs through a chemical reaction, resulting in higher penetration depth and best sensitivity. However both natural and artificial chemiluminescent systems require a continuous flow of exogenous reactants since all substrates are irreversibly consumed. BioPoweredCL aims to develop an unprecedented strategy to enable molecular imaging by realizing near infrared luminophores that harvest energy from the cellular respiration chain, in order to emit light without being consumed themselves. BioPoweredCL takes advantage of the most recent progress in artificial light production to develop a novel imaging technique where the absence of an excitation source overcomes the current limitations of fluorescence imaging while the regeneration of the luminophore overcomes the limitations of bioluminescence imaging. If successful it could replace current techniques based on harmful ionizing radiations such as X-rays or γ-rays. To reach such a grand-challenge the work plan is articulated into three different phases: 1) synthesis of new luminophores; 2) electrochemical characterization and energy cell harvesting; 3) in vitro experiments where the full potential of the approach will be validated.
Summary
Imaging is one of the most powerful technique to visualize molecules, tissues, to understand and follow processes and it is the most used diagnostic tool in vitro and in vivo, Current biomedical imaging techniques can have high sensitivity, good spatial/temporal resolution and, in some cases, high tissue penetration but cannot combine all of these desired properties without using harmful radiations (or toxic labels) or very expensive equipment. Optical imaging techniques represent the best compromise among them; however, their ability to scale to human body is precluded. The main restriction of fluorescence imaging is that it requires light excitation which is limited by tissue absorption and scattering. Such limitations are not present in chemiluminescence imaging since light production occurs through a chemical reaction, resulting in higher penetration depth and best sensitivity. However both natural and artificial chemiluminescent systems require a continuous flow of exogenous reactants since all substrates are irreversibly consumed. BioPoweredCL aims to develop an unprecedented strategy to enable molecular imaging by realizing near infrared luminophores that harvest energy from the cellular respiration chain, in order to emit light without being consumed themselves. BioPoweredCL takes advantage of the most recent progress in artificial light production to develop a novel imaging technique where the absence of an excitation source overcomes the current limitations of fluorescence imaging while the regeneration of the luminophore overcomes the limitations of bioluminescence imaging. If successful it could replace current techniques based on harmful ionizing radiations such as X-rays or γ-rays. To reach such a grand-challenge the work plan is articulated into three different phases: 1) synthesis of new luminophores; 2) electrochemical characterization and energy cell harvesting; 3) in vitro experiments where the full potential of the approach will be validated.
Max ERC Funding
1 449 750 €
Duration
Start date: 2021-10-01, End date: 2026-09-30
Project acronym BUNDLEFORCE
Project Unravelling the Mechanosensitivity of Actin Bundles in Filopodia
Researcher (PI) Antoine Guillaume Jegou
Host Institution (HI) CENTRE NATIONAL DE LA RECHERCHE SCIENTIFIQUE CNRS
Country France
Call Details Starting Grant (StG), LS1, ERC-2015-STG
Summary Eukaryotic cells constantly convert signals between biochemical energy and mechanical work to timely accomplish many key functions such as migration, division or development. Filopodia are essential finger-like structures that emerge at the cell front to orient the cell in response to its chemical and mechanical environment. Yet, the molecular interactions that make the filopodia mechanosensitive are not known. To tackle this challenge we propose unique biophysical in vitro and in vivo experiments of increasing complexity. Here we will focus on how the underlying actin filament bundle regulates filopodium growth and retraction cycles at the micrometer and seconds scales. These parallel actin filaments are mainly elongated at their barbed-end by formins and cross-linked by bundling proteins such as fascins.
We aim to:
1) Elucidate how formin and fascin functions are regulated by mechanics at the single filament level. We will investigate how formin partners and competitors present in filopodia affect formin processivity; how fascin affinity for the side of filaments is modified by filament tension and formin presence at the barbed-end.
2) Reconstitute filopodium-like actin bundles in vitro to understand how actin bundle size and fate are regulated down to the molecular scale. Using a unique experimental setup that combines microfluidics and optical tweezers, we will uncover for the first time actin bundles mechanosensitive capabilities, both in tension and compression.
3) Decipher in vivo the mechanics of actin bundles in filopodia, using fascins and formins with integrated fluorescent tension sensors.
This framework spanning from in vitro single filament to in vivo meso-scale actin networks will bring unprecedented insights into the role of actin bundles in filopodia mechanosensitivity.
Summary
Eukaryotic cells constantly convert signals between biochemical energy and mechanical work to timely accomplish many key functions such as migration, division or development. Filopodia are essential finger-like structures that emerge at the cell front to orient the cell in response to its chemical and mechanical environment. Yet, the molecular interactions that make the filopodia mechanosensitive are not known. To tackle this challenge we propose unique biophysical in vitro and in vivo experiments of increasing complexity. Here we will focus on how the underlying actin filament bundle regulates filopodium growth and retraction cycles at the micrometer and seconds scales. These parallel actin filaments are mainly elongated at their barbed-end by formins and cross-linked by bundling proteins such as fascins.
We aim to:
1) Elucidate how formin and fascin functions are regulated by mechanics at the single filament level. We will investigate how formin partners and competitors present in filopodia affect formin processivity; how fascin affinity for the side of filaments is modified by filament tension and formin presence at the barbed-end.
2) Reconstitute filopodium-like actin bundles in vitro to understand how actin bundle size and fate are regulated down to the molecular scale. Using a unique experimental setup that combines microfluidics and optical tweezers, we will uncover for the first time actin bundles mechanosensitive capabilities, both in tension and compression.
3) Decipher in vivo the mechanics of actin bundles in filopodia, using fascins and formins with integrated fluorescent tension sensors.
This framework spanning from in vitro single filament to in vivo meso-scale actin networks will bring unprecedented insights into the role of actin bundles in filopodia mechanosensitivity.
Max ERC Funding
1 499 190 €
Duration
Start date: 2016-03-01, End date: 2021-08-31
Project acronym CALI
Project The Cambodian Archaeological Lidar Initiative: Exploring Resilience in the Engineered Landscapes of Early SE Asia
Researcher (PI) Damian Evans
Host Institution (HI) ECOLE FRANCAISE D'EXTREME-ORIENT
Country France
Call Details Starting Grant (StG), SH6, ERC-2014-STG
Summary For over half a millennium, the great medieval capital of Angkor lay at the heart of a vast empire stretching across much of mainland SE Asia. Recent research has revealed that the famous monuments of Angkor were merely the epicentre of an immense settlement complex, with highly elaborate engineering works designed to manage water and mitigate the uncertainty of monsoon rains. Compelling evidence is now emerging that other temple complexes of the medieval Khmer Empire may also have formed the urban cores of dispersed, low-density settlements with similar systems of hydraulic engineering.
Using innovative airborne laser scanning (‘lidar’) technology, CALI will uncover, map and compare archaeological landscapes around all the major temple complexes of Cambodia, with a view to understanding what role these complex and vulnerable water management schemes played in the growth and decline of early civilisations in SE Asia. CALI will evaluate the hypothesis that the Khmer civilisation, in a bid to overcome the inherent constraints of a monsoon environment, became locked into rigid and inflexible traditions of urban development and large-scale hydraulic engineering that constrained their ability to adapt to rapidly-changing social, political and environmental circumstances.
By integrating data and techniques from fast-developing archaeological sciences like remote sensing, palaeoclimatology and geoinformatics, this work will provide important insights into the reasons for the collapse of inland agrarian empires in the middle of the second millennium AD, a transition that marks the emergence of modern mainland SE Asia. The lidar data will provide a comprehensive and internally-consistent archive of urban form at a regional scale, and offer a unique experimental space for evaluating socio-ecological resilience, persistence and transformation over two thousand years of human history, with clear implications for our understanding of contemporary urbanism and of urban futures.
Summary
For over half a millennium, the great medieval capital of Angkor lay at the heart of a vast empire stretching across much of mainland SE Asia. Recent research has revealed that the famous monuments of Angkor were merely the epicentre of an immense settlement complex, with highly elaborate engineering works designed to manage water and mitigate the uncertainty of monsoon rains. Compelling evidence is now emerging that other temple complexes of the medieval Khmer Empire may also have formed the urban cores of dispersed, low-density settlements with similar systems of hydraulic engineering.
Using innovative airborne laser scanning (‘lidar’) technology, CALI will uncover, map and compare archaeological landscapes around all the major temple complexes of Cambodia, with a view to understanding what role these complex and vulnerable water management schemes played in the growth and decline of early civilisations in SE Asia. CALI will evaluate the hypothesis that the Khmer civilisation, in a bid to overcome the inherent constraints of a monsoon environment, became locked into rigid and inflexible traditions of urban development and large-scale hydraulic engineering that constrained their ability to adapt to rapidly-changing social, political and environmental circumstances.
By integrating data and techniques from fast-developing archaeological sciences like remote sensing, palaeoclimatology and geoinformatics, this work will provide important insights into the reasons for the collapse of inland agrarian empires in the middle of the second millennium AD, a transition that marks the emergence of modern mainland SE Asia. The lidar data will provide a comprehensive and internally-consistent archive of urban form at a regional scale, and offer a unique experimental space for evaluating socio-ecological resilience, persistence and transformation over two thousand years of human history, with clear implications for our understanding of contemporary urbanism and of urban futures.
Max ERC Funding
1 482 844 €
Duration
Start date: 2015-03-01, End date: 2020-02-29
