Project acronym 2F4BIODYN
Project Two-Field Nuclear Magnetic Resonance Spectroscopy for the Exploration of Biomolecular Dynamics
Researcher (PI) Fabien Ferrage
Host Institution (HI) CENTRE NATIONAL DE LA RECHERCHE SCIENTIFIQUE CNRS
Call Details Starting Grant (StG), PE4, ERC-2011-StG_20101014
Summary The paradigm of the structure-function relationship in proteins is outdated. Biological macromolecules and supramolecular assemblies are highly dynamic objects. Evidence that their motions are of utmost importance to their functions is regularly identified. The understanding of the physical chemistry of biological processes at an atomic level has to rely not only on the description of structure but also on the characterization of molecular motions.
The investigation of protein motions will be undertaken with a very innovative methodological approach in nuclear magnetic resonance relaxation. In order to widen the ranges of frequencies at which local motions in proteins are probed, we will first use and develop new techniques for a prototype shuttle system for the measurement of relaxation at low fields on a high-field NMR spectrometer. Second, we will develop a novel system: a set of low-field NMR spectrometers designed as accessories for high-field spectrometers. Used in conjunction with the shuttle, this system will offer (i) the sensitivity and resolution (i.e. atomic level information) of a high-field spectrometer (ii) the access to low fields of a relaxometer and (iii) the ability to measure a wide variety of relaxation rates with high accuracy. This system will benefit from the latest technology in homogeneous permanent magnet development to allow a control of spin systems identical to that of a high-resolution probe. This new apparatus will open the way to the use of NMR relaxation at low fields for the refinement of protein motions at an atomic scale.
Applications of this novel approach will focus on the bright side of protein dynamics: (i) the largely unexplored dynamics of intrinsically disordered proteins, and (ii) domain motions in large proteins. In both cases, we will investigate a series of diverse protein systems with implications in development, cancer and immunity.
Summary
The paradigm of the structure-function relationship in proteins is outdated. Biological macromolecules and supramolecular assemblies are highly dynamic objects. Evidence that their motions are of utmost importance to their functions is regularly identified. The understanding of the physical chemistry of biological processes at an atomic level has to rely not only on the description of structure but also on the characterization of molecular motions.
The investigation of protein motions will be undertaken with a very innovative methodological approach in nuclear magnetic resonance relaxation. In order to widen the ranges of frequencies at which local motions in proteins are probed, we will first use and develop new techniques for a prototype shuttle system for the measurement of relaxation at low fields on a high-field NMR spectrometer. Second, we will develop a novel system: a set of low-field NMR spectrometers designed as accessories for high-field spectrometers. Used in conjunction with the shuttle, this system will offer (i) the sensitivity and resolution (i.e. atomic level information) of a high-field spectrometer (ii) the access to low fields of a relaxometer and (iii) the ability to measure a wide variety of relaxation rates with high accuracy. This system will benefit from the latest technology in homogeneous permanent magnet development to allow a control of spin systems identical to that of a high-resolution probe. This new apparatus will open the way to the use of NMR relaxation at low fields for the refinement of protein motions at an atomic scale.
Applications of this novel approach will focus on the bright side of protein dynamics: (i) the largely unexplored dynamics of intrinsically disordered proteins, and (ii) domain motions in large proteins. In both cases, we will investigate a series of diverse protein systems with implications in development, cancer and immunity.
Max ERC Funding
1 462 080 €
Duration
Start date: 2012-01-01, End date: 2017-12-31
Project acronym A-LIFE
Project The asymmetry of life: towards a unified view of the emergence of biological homochirality
Researcher (PI) Cornelia MEINERT
Host Institution (HI) CENTRE NATIONAL DE LA RECHERCHE SCIENTIFIQUE CNRS
Call Details Starting Grant (StG), PE4, ERC-2018-STG
Summary What is responsible for the emergence of homochirality, the almost exclusive use of one enantiomer over its mirror image? And what led to the evolution of life’s homochiral biopolymers, DNA/RNA, proteins and lipids, where all the constituent monomers exhibit the same handedness?
Based on in-situ observations and laboratory studies, we propose that this handedness occurs when chiral biomolecules are synthesized asymmetrically through interaction with circularly polarized photons in interstellar space. The ultimate goal of this project will be to demonstrate how the diverse set of heterogeneous enantioenriched molecules, available from meteoritic impact, assembles into homochiral pre-biopolymers, by simulating the evolutionary stages on early Earth. My recent research has shown that the central chiral unit of RNA, ribose, forms readily under simulated comet conditions and this has provided valuable new insights into the accessibility of precursors of genetic material in interstellar environments. The significance of this project arises due to the current lack of experimental demonstration that amino acids, sugars and lipids can simultaneously and asymmetrically be synthesized by a universal physical selection process.
A synergistic methodology will be developed to build a unified theory for the origin of all chiral biological building blocks and their assembly into homochiral supramolecular entities. For the first time, advanced analyses of astrophysical-relevant samples, asymmetric photochemistry triggered by circularly polarized synchrotron and laser sources, and chiral amplification due to polymerization processes will be combined. Intermediates and autocatalytic reaction kinetics will be monitored and supported by quantum calculations to understand the underlying processes. A unified theory on the asymmetric formation and self-assembly of life’s biopolymers is groundbreaking and will impact the whole conceptual foundation of the origin of life.
Summary
What is responsible for the emergence of homochirality, the almost exclusive use of one enantiomer over its mirror image? And what led to the evolution of life’s homochiral biopolymers, DNA/RNA, proteins and lipids, where all the constituent monomers exhibit the same handedness?
Based on in-situ observations and laboratory studies, we propose that this handedness occurs when chiral biomolecules are synthesized asymmetrically through interaction with circularly polarized photons in interstellar space. The ultimate goal of this project will be to demonstrate how the diverse set of heterogeneous enantioenriched molecules, available from meteoritic impact, assembles into homochiral pre-biopolymers, by simulating the evolutionary stages on early Earth. My recent research has shown that the central chiral unit of RNA, ribose, forms readily under simulated comet conditions and this has provided valuable new insights into the accessibility of precursors of genetic material in interstellar environments. The significance of this project arises due to the current lack of experimental demonstration that amino acids, sugars and lipids can simultaneously and asymmetrically be synthesized by a universal physical selection process.
A synergistic methodology will be developed to build a unified theory for the origin of all chiral biological building blocks and their assembly into homochiral supramolecular entities. For the first time, advanced analyses of astrophysical-relevant samples, asymmetric photochemistry triggered by circularly polarized synchrotron and laser sources, and chiral amplification due to polymerization processes will be combined. Intermediates and autocatalytic reaction kinetics will be monitored and supported by quantum calculations to understand the underlying processes. A unified theory on the asymmetric formation and self-assembly of life’s biopolymers is groundbreaking and will impact the whole conceptual foundation of the origin of life.
Max ERC Funding
1 500 000 €
Duration
Start date: 2019-04-01, End date: 2024-03-31
Project acronym ABIOS
Project ABIOtic Synthesis of RNA: an investigation on how life started before biology existed
Researcher (PI) Guillaume STIRNEMANN
Host Institution (HI) CENTRE NATIONAL DE LA RECHERCHE SCIENTIFIQUE CNRS
Call Details Starting Grant (StG), PE4, ERC-2017-STG
Summary The emergence of life is one of the most fascinating and yet largely unsolved questions in the natural sciences, and thus a significant challenge for scientists from many disciplines. There is growing evidence that ribonucleic acid (RNA) polymers, which are capable of genetic information storage and self-catalysis, were involved in the early forms of life. But despite recent progress, RNA synthesis without biological machineries is very challenging. The current project aims at understanding how to synthesize RNA in abiotic conditions. I will solve problems associated with three critical aspects of RNA formation that I will rationalize at a molecular level: (i) accumulation of precursors, (ii) formation of a chemical bond between RNA monomers, and (iii) tolerance for alternative backbone sugars or linkages. Because I will study problems ranging from the formation of chemical bonds up to the stability of large biopolymers, I propose an original computational multi-scale approach combining techniques that range from quantum calculations to large-scale all-atom simulations, employed together with efficient enhanced-sampling algorithms, forcefield improvement, cutting-edge analysis methods and model development.
My objectives are the following:
1 • To explain why the poorly-understood thermally-driven process of thermophoresis can contribute to the accumulation of dilute precursors.
2 • To understand why linking RNA monomers with phosphoester bonds is so difficult, to understand the molecular mechanism of possible catalysts and to suggest key improvements.
3 • To rationalize the molecular basis for RNA tolerance for alternative backbone sugars or linkages that have probably been incorporated in abiotic conditions.
This unique in-silico laboratory setup should significantly impact our comprehension of life’s origin by overcoming major obstacles to RNA abiotic formation, and in addition will reveal significant orthogonal outcomes for (bio)technological applications.
Summary
The emergence of life is one of the most fascinating and yet largely unsolved questions in the natural sciences, and thus a significant challenge for scientists from many disciplines. There is growing evidence that ribonucleic acid (RNA) polymers, which are capable of genetic information storage and self-catalysis, were involved in the early forms of life. But despite recent progress, RNA synthesis without biological machineries is very challenging. The current project aims at understanding how to synthesize RNA in abiotic conditions. I will solve problems associated with three critical aspects of RNA formation that I will rationalize at a molecular level: (i) accumulation of precursors, (ii) formation of a chemical bond between RNA monomers, and (iii) tolerance for alternative backbone sugars or linkages. Because I will study problems ranging from the formation of chemical bonds up to the stability of large biopolymers, I propose an original computational multi-scale approach combining techniques that range from quantum calculations to large-scale all-atom simulations, employed together with efficient enhanced-sampling algorithms, forcefield improvement, cutting-edge analysis methods and model development.
My objectives are the following:
1 • To explain why the poorly-understood thermally-driven process of thermophoresis can contribute to the accumulation of dilute precursors.
2 • To understand why linking RNA monomers with phosphoester bonds is so difficult, to understand the molecular mechanism of possible catalysts and to suggest key improvements.
3 • To rationalize the molecular basis for RNA tolerance for alternative backbone sugars or linkages that have probably been incorporated in abiotic conditions.
This unique in-silico laboratory setup should significantly impact our comprehension of life’s origin by overcoming major obstacles to RNA abiotic formation, and in addition will reveal significant orthogonal outcomes for (bio)technological applications.
Max ERC Funding
1 497 031 €
Duration
Start date: 2018-02-01, End date: 2023-01-31
Project acronym ACAP
Project Acency Costs and Asset Pricing
Researcher (PI) Thomas Mariotti
Host Institution (HI) FONDATION JEAN-JACQUES LAFFONT,TOULOUSE SCIENCES ECONOMIQUES
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 AIME
Project An Inquiry into Modes of Existence
Researcher (PI) Bruno Latour
Host Institution (HI) FONDATION NATIONALE DES SCIENCES POLITIQUES
Call Details Advanced Grant (AdG), SH2, ERC-2010-AdG_20100407
Summary "AIME is an inquiry to make more precise what is lumped together into the confusing word ""modernization"". The work done in the field of science studies (STS) on the progress and practice of science and technology has had the consequence of deeply modifying the definition of ""modernity"", resulting into the provocative idea that ""we (meaning the Europeans) have never been modern"". This is, however only a negative definition. To obtain a positive rendering of the European current situation, it is necessary to start an inquiry in the complex and conflicting set of values that have been invented. This inquiry is possible only if there is a clear and shareable way to judge the differences in the set of truth-conditions that make up those conflicting sets of values. AIME offers a grammar of those differences based on the key notion of modes of existence. Then it builds a procedure and an instrument to test this grammar into a selected set of situations where the definitions of the differing modes of existence is redefined and renegotiated. The result is a set of shareable definitions of what modernization has been in practice. This is important just at the moment when Europe has lost its privileged status and needs to be able to present itself in a new ways to the other cultures and civilizations which are making up the world of globalization with very different views on what it is to modernize themselves."
Summary
"AIME is an inquiry to make more precise what is lumped together into the confusing word ""modernization"". The work done in the field of science studies (STS) on the progress and practice of science and technology has had the consequence of deeply modifying the definition of ""modernity"", resulting into the provocative idea that ""we (meaning the Europeans) have never been modern"". This is, however only a negative definition. To obtain a positive rendering of the European current situation, it is necessary to start an inquiry in the complex and conflicting set of values that have been invented. This inquiry is possible only if there is a clear and shareable way to judge the differences in the set of truth-conditions that make up those conflicting sets of values. AIME offers a grammar of those differences based on the key notion of modes of existence. Then it builds a procedure and an instrument to test this grammar into a selected set of situations where the definitions of the differing modes of existence is redefined and renegotiated. The result is a set of shareable definitions of what modernization has been in practice. This is important just at the moment when Europe has lost its privileged status and needs to be able to present itself in a new ways to the other cultures and civilizations which are making up the world of globalization with very different views on what it is to modernize themselves."
Max ERC Funding
1 334 720 €
Duration
Start date: 2011-09-01, End date: 2015-06-30
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
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: 2020-02-29
Project acronym AMPERE
Project Accounting for Metallicity, Polarization of the Electrolyte, and Redox reactions in computational Electrochemistry
Researcher (PI) Mathieu Eric Salanne
Host Institution (HI) SORBONNE UNIVERSITE
Call Details Consolidator Grant (CoG), PE4, ERC-2017-COG
Summary Applied electrochemistry plays a key role in many technologies, such as batteries, fuel cells, supercapacitors or solar cells. It is therefore at the core of many research programs all over the world. Yet, fundamental electrochemical investigations remain scarce. In particular, electrochemistry is among the fields for which the gap between theory and experiment is the largest. From the computational point of view, there is no molecular dynamics (MD) software devoted to the simulation of electrochemical systems while other fields such as biochemistry (GROMACS) or material science (LAMMPS) have dedicated tools. This is due to the difficulty of accounting for complex effects arising from (i) the degree of metallicity of the electrode (i.e. from semimetals to perfect conductors), (ii) the mutual polarization occurring at the electrode/electrolyte interface and (iii) the redox reactivity through explicit electron transfers. Current understanding therefore relies on standard theories that derive from an inaccurate molecular-scale picture. My objective is to fill this gap by introducing a whole set of new methods for simulating electrochemical systems. They will be provided to the computational electrochemistry community as a cutting-edge MD software adapted to supercomputers. First applications will aim at the discovery of new electrolytes for energy storage. Here I will focus on (1) ‘‘water-in-salts’’ to understand why these revolutionary liquids enable much higher voltage than conventional solutions (2) redox reactions inside a nanoporous electrode to support the development of future capacitive energy storage devices. These selected applications are timely and rely on collaborations with leading experimental partners. The results are expected to shed an unprecedented light on the importance of polarization effects on the structure and the reactivity of electrode/electrolyte interfaces, establishing MD as a prominent tool for solving complex electrochemistry problems.
Summary
Applied electrochemistry plays a key role in many technologies, such as batteries, fuel cells, supercapacitors or solar cells. It is therefore at the core of many research programs all over the world. Yet, fundamental electrochemical investigations remain scarce. In particular, electrochemistry is among the fields for which the gap between theory and experiment is the largest. From the computational point of view, there is no molecular dynamics (MD) software devoted to the simulation of electrochemical systems while other fields such as biochemistry (GROMACS) or material science (LAMMPS) have dedicated tools. This is due to the difficulty of accounting for complex effects arising from (i) the degree of metallicity of the electrode (i.e. from semimetals to perfect conductors), (ii) the mutual polarization occurring at the electrode/electrolyte interface and (iii) the redox reactivity through explicit electron transfers. Current understanding therefore relies on standard theories that derive from an inaccurate molecular-scale picture. My objective is to fill this gap by introducing a whole set of new methods for simulating electrochemical systems. They will be provided to the computational electrochemistry community as a cutting-edge MD software adapted to supercomputers. First applications will aim at the discovery of new electrolytes for energy storage. Here I will focus on (1) ‘‘water-in-salts’’ to understand why these revolutionary liquids enable much higher voltage than conventional solutions (2) redox reactions inside a nanoporous electrode to support the development of future capacitive energy storage devices. These selected applications are timely and rely on collaborations with leading experimental partners. The results are expected to shed an unprecedented light on the importance of polarization effects on the structure and the reactivity of electrode/electrolyte interfaces, establishing MD as a prominent tool for solving complex electrochemistry problems.
Max ERC Funding
1 588 769 €
Duration
Start date: 2018-04-01, End date: 2023-03-31
Project acronym ANTIViR
Project Molecular mechanisms of interferon-induced antiviral restriction and signalling
Researcher (PI) Caroline GOUJON
Host Institution (HI) INSTITUT NATIONAL DE LA SANTE ET DE LA RECHERCHE MEDICALE
Call Details Starting Grant (StG), LS6, ERC-2017-STG
Summary Interferons (IFNs), which are signalling proteins produced by infected cells, are the first line of defence against viral infections. IFNs induce, in infected and neighbouring cells, the expression of hundreds of IFN-stimulated genes (ISGs). The ISGs in turn induce in cells a potent antiviral state, capable of preventing replication of most viruses, including Human Immunodeficiency Virus type 1 (HIV-1) and influenza A virus (FLUAV). Identifying the antiviral ISGs and understanding their mechanisms of action is therefore crucial to progress in the fight against viruses.
ISGs playing a role in the antiviral state have been identified, such as human MX1, a well-known antiviral factor able to restrict numerous viruses including FLUAV, and MX2, an HIV-1 inhibitor. Both proteins bind to viral components but their detailed mechanisms of action, as well as the consequences of restriction on the activation of the innate immune system, remain unclear. Moreover, our preliminary work shows that additional anti-HIV-1 and anti-FLUAV ISGs remain to identify.
In this context, this proposal seeks an ERC StG funding to explore 3 major aims: 1) unravelling the mechanisms of antiviral action of MX proteins, by taking advantage of their similar structure and engineered chimeric proteins, and by using functional genetic screens to identify their cofactors; 2) investigating the consequences of incoming virus recognition by MX proteins on innate immune signalling, by altering their expression in target cells and measuring the cell response in terms of gene induction and cytokine production; 3) identifying and characterizing new ISGs able to inhibit viral replication with a combination of powerful approaches, including a whole-genome CRISPR/Cas9 knock-out screen.
Overall, this proposal will provide a better understanding of the molecular mechanisms involved in the antiviral effect of IFN, and may guide future efforts to identify novel therapeutic targets against major pathogenic viruses.
Summary
Interferons (IFNs), which are signalling proteins produced by infected cells, are the first line of defence against viral infections. IFNs induce, in infected and neighbouring cells, the expression of hundreds of IFN-stimulated genes (ISGs). The ISGs in turn induce in cells a potent antiviral state, capable of preventing replication of most viruses, including Human Immunodeficiency Virus type 1 (HIV-1) and influenza A virus (FLUAV). Identifying the antiviral ISGs and understanding their mechanisms of action is therefore crucial to progress in the fight against viruses.
ISGs playing a role in the antiviral state have been identified, such as human MX1, a well-known antiviral factor able to restrict numerous viruses including FLUAV, and MX2, an HIV-1 inhibitor. Both proteins bind to viral components but their detailed mechanisms of action, as well as the consequences of restriction on the activation of the innate immune system, remain unclear. Moreover, our preliminary work shows that additional anti-HIV-1 and anti-FLUAV ISGs remain to identify.
In this context, this proposal seeks an ERC StG funding to explore 3 major aims: 1) unravelling the mechanisms of antiviral action of MX proteins, by taking advantage of their similar structure and engineered chimeric proteins, and by using functional genetic screens to identify their cofactors; 2) investigating the consequences of incoming virus recognition by MX proteins on innate immune signalling, by altering their expression in target cells and measuring the cell response in terms of gene induction and cytokine production; 3) identifying and characterizing new ISGs able to inhibit viral replication with a combination of powerful approaches, including a whole-genome CRISPR/Cas9 knock-out screen.
Overall, this proposal will provide a better understanding of the molecular mechanisms involved in the antiviral effect of IFN, and may guide future efforts to identify novel therapeutic targets against major pathogenic viruses.
Max ERC Funding
1 499 794 €
Duration
Start date: 2017-12-01, End date: 2022-11-30
Project acronym ANTIVIRALRNAI
Project RNAi-mediated viral immunity in insects
Researcher (PI) Maria-Carla Saleh
Host Institution (HI) INSTITUT PASTEUR
Call Details Starting Grant (StG), LS6, ERC-2009-StG
Summary RNA interference (RNAi) is a conserved sequence-specific, gene-silencing mechanism that is induced by double-stranded RNA (dsRNA). One of the functions of this pathway is the defense against parasitic nucleic acids: transposons and viruses. Previous results demonstrated that viral infections in Drosophila melanogaster are fought by an antiviral RNAi response and that components of the endocytic pathway are required for dsRNA entry to initiate the RNAi response. Recently we have shown that infected insect cells spread a systemic silencing signal that elicits a protective RNAi-dependent immunity throughout the organism. This suggests that the cell-autonomous RNAi response is insufficient to control a viral infection and that flies also rely on systemic immune response to fight against such infections. As a junior group leader, I will study the mechanisms that mediate the RNAi-based antiviral response in insects. By combining biochemical, cellular, molecular and genomic approaches, both in vivo and in cell culture, I will analyze the mechanisms underlying viral tropism, systemic propagation of the antiviral signal and the basis of the persistence of the antiviral state. Furthermore, I will examine whether the dsRNA-uptake pathway is conserved in mosquitoes and its relationship with viral immunity in that host. This comprehensive approach will tackle how this nucleic acid-based immunity works in insects to generate an anti-viral stage. A better understanding of the role of RNA silencing in insects during virus infection will allow the exploitation of this pathway for improvement of public health related problems such as arbovirus infection and disease.
Summary
RNA interference (RNAi) is a conserved sequence-specific, gene-silencing mechanism that is induced by double-stranded RNA (dsRNA). One of the functions of this pathway is the defense against parasitic nucleic acids: transposons and viruses. Previous results demonstrated that viral infections in Drosophila melanogaster are fought by an antiviral RNAi response and that components of the endocytic pathway are required for dsRNA entry to initiate the RNAi response. Recently we have shown that infected insect cells spread a systemic silencing signal that elicits a protective RNAi-dependent immunity throughout the organism. This suggests that the cell-autonomous RNAi response is insufficient to control a viral infection and that flies also rely on systemic immune response to fight against such infections. As a junior group leader, I will study the mechanisms that mediate the RNAi-based antiviral response in insects. By combining biochemical, cellular, molecular and genomic approaches, both in vivo and in cell culture, I will analyze the mechanisms underlying viral tropism, systemic propagation of the antiviral signal and the basis of the persistence of the antiviral state. Furthermore, I will examine whether the dsRNA-uptake pathway is conserved in mosquitoes and its relationship with viral immunity in that host. This comprehensive approach will tackle how this nucleic acid-based immunity works in insects to generate an anti-viral stage. A better understanding of the role of RNA silencing in insects during virus infection will allow the exploitation of this pathway for improvement of public health related problems such as arbovirus infection and disease.
Max ERC Funding
1 900 000 €
Duration
Start date: 2009-10-01, End date: 2014-12-31
Project acronym AQUARAMAN
Project Pipet Based Scanning Probe Microscopy Tip-Enhanced Raman Spectroscopy: A Novel Approach for TERS in Liquids
Researcher (PI) Aleix Garcia Guell
Host Institution (HI) ECOLE POLYTECHNIQUE
Call Details Starting Grant (StG), PE4, ERC-2016-STG
Summary Tip-enhanced Raman spectroscopy (TERS) is often described as the most powerful tool for optical characterization of surfaces and their proximities. It combines the intrinsic spatial resolution of scanning probe techniques (AFM or STM) with the chemical information content of vibrational Raman spectroscopy. Capable to reveal surface heterogeneity at the nanoscale, TERS is currently playing a fundamental role in the understanding of interfacial physicochemical processes in key areas of science and technology such as chemistry, biology and material science.
Unfortunately, the undeniable potential of TERS as a label-free tool for nanoscale chemical and structural characterization is, nowadays, limited to air and vacuum environments, with it failing to operate in a reliable and systematic manner in liquid. The reasons are more technical than fundamental, as what is hindering the application of TERS in water is, among other issues, the low stability of the probes and their consistency. Fields of science and technology where the presence of water/electrolyte is unavoidable, such as biology and electrochemistry, remain unexplored with this powerful technique.
We propose a revolutionary approach for TERS in liquids founded on the employment of pipet-based scanning probe microscopy techniques (pb-SPM) as an alternative to AFM and STM. The use of recent but well established pb-SPM brings the opportunity to develop unprecedented pipet-based TERS probes (beyond the classic and limited metallized solid probes from AFM and STM), together with the implementation of ingenious and innovative measures to enhance tip stability, sensitivity and reliability, unattainable with the current techniques.
We will be in possession of a unique nano-spectroscopy platform capable of experiments in liquids, to follow dynamic processes in-situ, addressing fundamental questions and bringing insight into interfacial phenomena spanning from materials science, physics, chemistry and biology.
Summary
Tip-enhanced Raman spectroscopy (TERS) is often described as the most powerful tool for optical characterization of surfaces and their proximities. It combines the intrinsic spatial resolution of scanning probe techniques (AFM or STM) with the chemical information content of vibrational Raman spectroscopy. Capable to reveal surface heterogeneity at the nanoscale, TERS is currently playing a fundamental role in the understanding of interfacial physicochemical processes in key areas of science and technology such as chemistry, biology and material science.
Unfortunately, the undeniable potential of TERS as a label-free tool for nanoscale chemical and structural characterization is, nowadays, limited to air and vacuum environments, with it failing to operate in a reliable and systematic manner in liquid. The reasons are more technical than fundamental, as what is hindering the application of TERS in water is, among other issues, the low stability of the probes and their consistency. Fields of science and technology where the presence of water/electrolyte is unavoidable, such as biology and electrochemistry, remain unexplored with this powerful technique.
We propose a revolutionary approach for TERS in liquids founded on the employment of pipet-based scanning probe microscopy techniques (pb-SPM) as an alternative to AFM and STM. The use of recent but well established pb-SPM brings the opportunity to develop unprecedented pipet-based TERS probes (beyond the classic and limited metallized solid probes from AFM and STM), together with the implementation of ingenious and innovative measures to enhance tip stability, sensitivity and reliability, unattainable with the current techniques.
We will be in possession of a unique nano-spectroscopy platform capable of experiments in liquids, to follow dynamic processes in-situ, addressing fundamental questions and bringing insight into interfacial phenomena spanning from materials science, physics, chemistry and biology.
Max ERC Funding
1 528 442 €
Duration
Start date: 2017-07-01, End date: 2022-06-30