Project acronym 14Constraint
Project Radiocarbon constraints for models of C cycling in terrestrial ecosystems: from process understanding to global benchmarking
Researcher (PI) Susan Trumbore
Host Institution (HI) MAX-PLANCK-GESELLSCHAFT ZUR FORDERUNG DER WISSENSCHAFTEN EV
Call Details Advanced Grant (AdG), PE10, ERC-2015-AdG
Summary The overall goal of 14Constraint is to enhance the availability and use of radiocarbon data as constraints for process-based understanding of the age distribution of carbon in and respired by soils and ecosystems. Carbon enters ecosystems by a single process, photosynthesis. It returns by a range of processes that depend on plant allocation and turnover, the efficiency and rate of litter decomposition and the mechanisms stabilizing C in soils. Thus the age distribution of respired CO2 and the age of C residing in plants, litter and soils are diagnostic properties of ecosystems that provide key constraints for testing carbon cycle models. Radiocarbon, especially the transit of ‘bomb’ 14C created in the 1960s, is a powerful tool for tracing C exchange on decadal to centennial timescales. 14Constraint will assemble a global database of existing radiocarbon data (WP1) and demonstrate how they can constrain and test ecosystem carbon cycle models. WP2 will fill data gaps and add new data from sites in key biomes that have ancillary data sufficient to construct belowground C and 14C budgets. These detailed investigations will focus on the role of time lags caused in necromass and fine roots, as well as the dynamics of deep soil C. Spatial extrapolation beyond the WP2 sites will require sampling along global gradients designed to explore the relative roles of mineralogy, vegetation and climate on the age of C in and respired from soil (WP3). Products of this 14Constraint will include the first publicly available global synthesis of terrestrial 14C data, and will add over 5000 new measurements. This project is urgently needed before atmospheric 14C levels decline to below 1950 levels as expected in the next decade.
Summary
The overall goal of 14Constraint is to enhance the availability and use of radiocarbon data as constraints for process-based understanding of the age distribution of carbon in and respired by soils and ecosystems. Carbon enters ecosystems by a single process, photosynthesis. It returns by a range of processes that depend on plant allocation and turnover, the efficiency and rate of litter decomposition and the mechanisms stabilizing C in soils. Thus the age distribution of respired CO2 and the age of C residing in plants, litter and soils are diagnostic properties of ecosystems that provide key constraints for testing carbon cycle models. Radiocarbon, especially the transit of ‘bomb’ 14C created in the 1960s, is a powerful tool for tracing C exchange on decadal to centennial timescales. 14Constraint will assemble a global database of existing radiocarbon data (WP1) and demonstrate how they can constrain and test ecosystem carbon cycle models. WP2 will fill data gaps and add new data from sites in key biomes that have ancillary data sufficient to construct belowground C and 14C budgets. These detailed investigations will focus on the role of time lags caused in necromass and fine roots, as well as the dynamics of deep soil C. Spatial extrapolation beyond the WP2 sites will require sampling along global gradients designed to explore the relative roles of mineralogy, vegetation and climate on the age of C in and respired from soil (WP3). Products of this 14Constraint will include the first publicly available global synthesis of terrestrial 14C data, and will add over 5000 new measurements. This project is urgently needed before atmospheric 14C levels decline to below 1950 levels as expected in the next decade.
Max ERC Funding
2 283 747 €
Duration
Start date: 2016-12-01, End date: 2021-11-30
Project acronym 3D_Tryps
Project The role of three-dimensional genome architecture in antigenic variation
Researcher (PI) Tim Nicolai SIEGEL
Host Institution (HI) LUDWIG-MAXIMILIANS-UNIVERSITAET MUENCHEN
Call Details Starting Grant (StG), LS6, ERC-2016-STG
Summary Antigenic variation is a widely employed strategy to evade the host immune response. It has similar functional requirements even in evolutionarily divergent pathogens. These include the mutually exclusive expression of antigens and the periodic, nonrandom switching in the expression of different antigens during the course of an infection. Despite decades of research the mechanisms of antigenic variation are not fully understood in any organism.
The recent development of high-throughput sequencing-based assays to probe the 3D genome architecture (Hi-C) has revealed the importance of the spatial organization of DNA inside the nucleus. 3D genome architecture plays a critical role in the regulation of mutually exclusive gene expression and the frequency of translocation between different genomic loci in many eukaryotes. Thus, genome architecture may also be a key regulator of antigenic variation, yet the causal links between genome architecture and the expression of antigens have not been studied systematically. In addition, the development of CRISPR-Cas9-based approaches to perform nucleotide-specific genome editing has opened unprecedented opportunities to study the influence of DNA sequence elements on the spatial organization of DNA and how this impacts antigen expression.
I have adapted both Hi-C and CRISPR-Cas9 technology to the protozoan parasite Trypanosoma brucei, one of the most important model organisms to study antigenic variation. These techniques will enable me to bridge the field of antigenic variation research with that of genome architecture. I will perform the first systematic analysis of the role of genome architecture in the mutually exclusive and hierarchical expression of antigens in any pathogen.
The experiments outlined in this proposal will provide new insight, facilitating a new view of antigenic variation and may eventually help medical intervention in T. brucei and in other pathogens relying on antigenic variation for their survival.
Summary
Antigenic variation is a widely employed strategy to evade the host immune response. It has similar functional requirements even in evolutionarily divergent pathogens. These include the mutually exclusive expression of antigens and the periodic, nonrandom switching in the expression of different antigens during the course of an infection. Despite decades of research the mechanisms of antigenic variation are not fully understood in any organism.
The recent development of high-throughput sequencing-based assays to probe the 3D genome architecture (Hi-C) has revealed the importance of the spatial organization of DNA inside the nucleus. 3D genome architecture plays a critical role in the regulation of mutually exclusive gene expression and the frequency of translocation between different genomic loci in many eukaryotes. Thus, genome architecture may also be a key regulator of antigenic variation, yet the causal links between genome architecture and the expression of antigens have not been studied systematically. In addition, the development of CRISPR-Cas9-based approaches to perform nucleotide-specific genome editing has opened unprecedented opportunities to study the influence of DNA sequence elements on the spatial organization of DNA and how this impacts antigen expression.
I have adapted both Hi-C and CRISPR-Cas9 technology to the protozoan parasite Trypanosoma brucei, one of the most important model organisms to study antigenic variation. These techniques will enable me to bridge the field of antigenic variation research with that of genome architecture. I will perform the first systematic analysis of the role of genome architecture in the mutually exclusive and hierarchical expression of antigens in any pathogen.
The experiments outlined in this proposal will provide new insight, facilitating a new view of antigenic variation and may eventually help medical intervention in T. brucei and in other pathogens relying on antigenic variation for their survival.
Max ERC Funding
1 498 175 €
Duration
Start date: 2017-04-01, End date: 2022-03-31
Project acronym A2C2
Project Atmospheric flow Analogues and Climate Change
Researcher (PI) Pascal Yiou
Host Institution (HI) COMMISSARIAT A L ENERGIE ATOMIQUE ET AUX ENERGIES ALTERNATIVES
Call Details Advanced Grant (AdG), PE10, ERC-2013-ADG
Summary "The A2C2 project treats two major challenges in climate and atmospheric research: the time dependence of the climate attractor to external forcings (solar, volcanic eruptions and anthropogenic), and the attribution of extreme climate events occurring in the northern extra-tropics. The main difficulties are the limited climate information, the computer cost of model simulations, and mathematical assumptions that are hardly verified and often overlooked in the literature.
A2C2 proposes a practical framework to overcome those three difficulties, linking the theory of dynamical systems and statistics. We will generalize the methodology of flow analogues to multiple databases in order to obtain probabilistic descriptions of analogue decompositions.
The project is divided into three workpackages (WP). WP1 embeds the analogue method in the theory of dynamical systems in order to provide a metric of an attractor deformation in time. The important methodological step is to detect trends or persisting outliers in the dates and scores of analogues when the system yields time-varying forcings. This is done from idealized models and full size climate models in which the forcings (anthropogenic and natural) are known.
A2C2 creates an open source toolkit to compute flow analogues from a wide array of databases (WP2). WP3 treats the two scientific challenges with the analogue method and multiple model ensembles, hence allowing uncertainty estimates under realistic mathematical hypotheses. The flow analogue methodology allows a systematic and quasi real-time analysis of extreme events, which is currently out of the reach of conventional climate modeling approaches.
The major breakthrough of A2C2 is to bridge the gap between operational needs (the immediate analysis of climate events) and the understanding long-term climate changes. A2C2 opens new research horizons for the exploitation of ensembles of simulations and reliable estimates of uncertainty."
Summary
"The A2C2 project treats two major challenges in climate and atmospheric research: the time dependence of the climate attractor to external forcings (solar, volcanic eruptions and anthropogenic), and the attribution of extreme climate events occurring in the northern extra-tropics. The main difficulties are the limited climate information, the computer cost of model simulations, and mathematical assumptions that are hardly verified and often overlooked in the literature.
A2C2 proposes a practical framework to overcome those three difficulties, linking the theory of dynamical systems and statistics. We will generalize the methodology of flow analogues to multiple databases in order to obtain probabilistic descriptions of analogue decompositions.
The project is divided into three workpackages (WP). WP1 embeds the analogue method in the theory of dynamical systems in order to provide a metric of an attractor deformation in time. The important methodological step is to detect trends or persisting outliers in the dates and scores of analogues when the system yields time-varying forcings. This is done from idealized models and full size climate models in which the forcings (anthropogenic and natural) are known.
A2C2 creates an open source toolkit to compute flow analogues from a wide array of databases (WP2). WP3 treats the two scientific challenges with the analogue method and multiple model ensembles, hence allowing uncertainty estimates under realistic mathematical hypotheses. The flow analogue methodology allows a systematic and quasi real-time analysis of extreme events, which is currently out of the reach of conventional climate modeling approaches.
The major breakthrough of A2C2 is to bridge the gap between operational needs (the immediate analysis of climate events) and the understanding long-term climate changes. A2C2 opens new research horizons for the exploitation of ensembles of simulations and reliable estimates of uncertainty."
Max ERC Funding
1 491 457 €
Duration
Start date: 2014-03-01, End date: 2019-02-28
Project acronym ABYSS
Project ABYSS - Assessment of bacterial life and matter cycling in deep-sea surface sediments
Researcher (PI) Antje Boetius
Host Institution (HI) ALFRED-WEGENER-INSTITUT HELMHOLTZ-ZENTRUM FUR POLAR- UND MEERESFORSCHUNG
Call Details Advanced Grant (AdG), LS8, ERC-2011-ADG_20110310
Summary The deep-sea floor hosts a distinct microbial biome covering 67% of the Earth’s surface, characterized by cold temperatures, permanent darkness, high pressure and food limitation. The surface sediments are dominated by bacteria, with on average a billion cells per ml. Benthic bacteria are highly relevant to the Earth’s element cycles as they remineralize most of the organic matter sinking from the productive surface ocean, and return nutrients, thereby promoting ocean primary production. What passes the bacterial filter is a relevant sink for carbon on geological time scales, influencing global oxygen and carbon budgets, and fueling the deep subsurface biosphere. Despite the relevance of deep-sea sediment bacteria to climate, geochemical cycles and ecology of the seafloor, their genetic and functional diversity, niche differentiation and biological interactions remain unknown. Our preliminary work in a global survey of deep-sea sediments enables us now to target specific genes for the quantification of abyssal bacteria. We can trace isotope-labeled elements into communities and single cells, and analyze the molecular alteration of organic matter during microbial degradation, all in context with environmental dynamics recorded at the only long-term deep-sea ecosystem observatory in the Arctic that we maintain. I propose to bridge biogeochemistry, ecology, microbiology and marine biology to develop a systematic understanding of abyssal sediment bacterial community distribution, diversity, function and interactions, by combining in situ flux studies and different visualization techniques with a wide range of molecular tools. Substantial progress is expected in understanding I) identity and function of the dominant types of indigenous benthic bacteria, II) dynamics in bacterial activity and diversity caused by variations in particle flux, III) interactions with different types and ages of organic matter, and other biological factors.
Summary
The deep-sea floor hosts a distinct microbial biome covering 67% of the Earth’s surface, characterized by cold temperatures, permanent darkness, high pressure and food limitation. The surface sediments are dominated by bacteria, with on average a billion cells per ml. Benthic bacteria are highly relevant to the Earth’s element cycles as they remineralize most of the organic matter sinking from the productive surface ocean, and return nutrients, thereby promoting ocean primary production. What passes the bacterial filter is a relevant sink for carbon on geological time scales, influencing global oxygen and carbon budgets, and fueling the deep subsurface biosphere. Despite the relevance of deep-sea sediment bacteria to climate, geochemical cycles and ecology of the seafloor, their genetic and functional diversity, niche differentiation and biological interactions remain unknown. Our preliminary work in a global survey of deep-sea sediments enables us now to target specific genes for the quantification of abyssal bacteria. We can trace isotope-labeled elements into communities and single cells, and analyze the molecular alteration of organic matter during microbial degradation, all in context with environmental dynamics recorded at the only long-term deep-sea ecosystem observatory in the Arctic that we maintain. I propose to bridge biogeochemistry, ecology, microbiology and marine biology to develop a systematic understanding of abyssal sediment bacterial community distribution, diversity, function and interactions, by combining in situ flux studies and different visualization techniques with a wide range of molecular tools. Substantial progress is expected in understanding I) identity and function of the dominant types of indigenous benthic bacteria, II) dynamics in bacterial activity and diversity caused by variations in particle flux, III) interactions with different types and ages of organic matter, and other biological factors.
Max ERC Funding
3 375 693 €
Duration
Start date: 2012-06-01, End date: 2018-05-31
Project acronym ACCLIMATE
Project Elucidating the Causes and Effects of Atlantic Circulation Changes through Model-Data Integration
Researcher (PI) Claire Waelbroeck
Host Institution (HI) CENTRE NATIONAL DE LA RECHERCHE SCIENTIFIQUE CNRS
Call Details Advanced Grant (AdG), PE10, ERC-2013-ADG
Summary Rapid changes in ocean circulation and climate have been observed in marine sediment and ice cores, notably over the last 60 thousand years (ky), highlighting the non-linear character of the climate system and underlining the possibility of rapid climate shifts in response to anthropogenic greenhouse gas forcing.
To date, these rapid changes in climate and ocean circulation are still not fully explained. Two main obstacles prevent going beyond the current state of knowledge:
- Paleoclimatic proxy data are by essence only indirect indicators of the climatic variables, and thus can not be directly compared with model outputs;
- A 4-D (latitude, longitude, water depth, time) reconstruction of Atlantic water masses over the past 40 ky is lacking: previous studies have generated isolated records with disparate timescales which do not allow the causes of circulation changes to be identified.
Overcoming these two major limitations will lead to major breakthroughs in climate research. Concretely, I will create the first database of Atlantic deep-sea records over the last 40 ky, and extract full climatic information from these records through an innovative model-data integration scheme using an isotopic proxy forward modeling approach. The novelty and exceptional potential of this scheme is twofold: (i) it avoids hypotheses on proxy interpretation and hence suppresses or strongly reduces the errors of interpretation of paleoclimatic records; (ii) it produces states of the climate system that best explain the observations over the last 40 ky, while being consistent with the model physics.
Expected results include:
• The elucidation of the mechanisms explaining rapid changes in ocean circulation and climate over the last 40 ky,
• Improved climate model physics and parameterizations,
• The first projections of future climate changes obtained with a model able to reproduce the highly non linear behavior of the climate system observed over the last 40 ky.
Summary
Rapid changes in ocean circulation and climate have been observed in marine sediment and ice cores, notably over the last 60 thousand years (ky), highlighting the non-linear character of the climate system and underlining the possibility of rapid climate shifts in response to anthropogenic greenhouse gas forcing.
To date, these rapid changes in climate and ocean circulation are still not fully explained. Two main obstacles prevent going beyond the current state of knowledge:
- Paleoclimatic proxy data are by essence only indirect indicators of the climatic variables, and thus can not be directly compared with model outputs;
- A 4-D (latitude, longitude, water depth, time) reconstruction of Atlantic water masses over the past 40 ky is lacking: previous studies have generated isolated records with disparate timescales which do not allow the causes of circulation changes to be identified.
Overcoming these two major limitations will lead to major breakthroughs in climate research. Concretely, I will create the first database of Atlantic deep-sea records over the last 40 ky, and extract full climatic information from these records through an innovative model-data integration scheme using an isotopic proxy forward modeling approach. The novelty and exceptional potential of this scheme is twofold: (i) it avoids hypotheses on proxy interpretation and hence suppresses or strongly reduces the errors of interpretation of paleoclimatic records; (ii) it produces states of the climate system that best explain the observations over the last 40 ky, while being consistent with the model physics.
Expected results include:
• The elucidation of the mechanisms explaining rapid changes in ocean circulation and climate over the last 40 ky,
• Improved climate model physics and parameterizations,
• The first projections of future climate changes obtained with a model able to reproduce the highly non linear behavior of the climate system observed over the last 40 ky.
Max ERC Funding
3 000 000 €
Duration
Start date: 2014-02-01, End date: 2019-01-31
Project acronym ACCRETE
Project Accretion and Early Differentiation of the Earth and Terrestrial Planets
Researcher (PI) David Crowhurst Rubie
Host Institution (HI) UNIVERSITAET BAYREUTH
Call Details Advanced Grant (AdG), PE10, ERC-2011-ADG_20110209
Summary Formation of the Earth and the other terrestrial planets of our Solar System (Mercury, Venus and Mars) commenced 4.568 billion years ago and occurred on a time scale of about 100 million years. These planets grew by the process of accretion, which involved numerous collisions with smaller (Moon- to Mars-size) bodies. Impacts with such bodies released sufficient energy to cause large-scale melting and the formation of deep “magma oceans”. Such magma oceans enabled liquid metal to separate from liquid silicate, sink and accumulate to form the metallic cores of the planets. Thus core formation in terrestrial planets was a multistage process, intimately related to the major impacts during accretion, that determined the chemistry of planetary mantles. However, until now, accretion, as modelled by astrophysicists, and core formation, as modelled by geochemists, have been treated as completely independent processes. The fundamental and crucial aim of this ambitious interdisciplinary proposal is to integrate astrophysical models of planetary accretion with geochemical models of planetary differentiation together with cosmochemical constraints obtained from meteorites. The research will involve integrating new models of planetary accretion with core formation models based on the partitioning of a large number of elements between liquid metal and liquid silicate that we will determine experimentally at pressures up to about 100 gigapascals (equivalent to 2400 km deep in the Earth). By comparing our results with the known physical and chemical characteristics of the terrestrial planets, we will obtain a comprehensive understanding of how these planets formed, grew and evolved, both physically and chemically, with time. The integration of chemistry and planetary differentiation with accretion models is a new ground-breaking concept that will lead, through synergies and feedback, to major new advances in the Earth and planetary sciences.
Summary
Formation of the Earth and the other terrestrial planets of our Solar System (Mercury, Venus and Mars) commenced 4.568 billion years ago and occurred on a time scale of about 100 million years. These planets grew by the process of accretion, which involved numerous collisions with smaller (Moon- to Mars-size) bodies. Impacts with such bodies released sufficient energy to cause large-scale melting and the formation of deep “magma oceans”. Such magma oceans enabled liquid metal to separate from liquid silicate, sink and accumulate to form the metallic cores of the planets. Thus core formation in terrestrial planets was a multistage process, intimately related to the major impacts during accretion, that determined the chemistry of planetary mantles. However, until now, accretion, as modelled by astrophysicists, and core formation, as modelled by geochemists, have been treated as completely independent processes. The fundamental and crucial aim of this ambitious interdisciplinary proposal is to integrate astrophysical models of planetary accretion with geochemical models of planetary differentiation together with cosmochemical constraints obtained from meteorites. The research will involve integrating new models of planetary accretion with core formation models based on the partitioning of a large number of elements between liquid metal and liquid silicate that we will determine experimentally at pressures up to about 100 gigapascals (equivalent to 2400 km deep in the Earth). By comparing our results with the known physical and chemical characteristics of the terrestrial planets, we will obtain a comprehensive understanding of how these planets formed, grew and evolved, both physically and chemically, with time. The integration of chemistry and planetary differentiation with accretion models is a new ground-breaking concept that will lead, through synergies and feedback, to major new advances in the Earth and planetary sciences.
Max ERC Funding
1 826 200 €
Duration
Start date: 2012-05-01, End date: 2018-04-30
Project acronym ACETOGENS
Project Acetogenic bacteria: from basic physiology via gene regulation to application in industrial biotechnology
Researcher (PI) Volker MÜLLER
Host Institution (HI) JOHANN WOLFGANG GOETHE-UNIVERSITATFRANKFURT AM MAIN
Call Details Advanced Grant (AdG), LS9, ERC-2016-ADG
Summary Demand for biofuels and other biologically derived commodities is growing worldwide as efforts increase to reduce reliance on fossil fuels and to limit climate change. Most commercial approaches rely on fermentations of organic matter with its inherent problems in producing CO2 and being in conflict with the food supply of humans. These problems are avoided if CO2 can be used as feedstock. Autotrophic organisms can fix CO2 by producing chemicals that are used as building blocks for the synthesis of cellular components (Biomass). Acetate-forming bacteria (acetogens) do neither require light nor oxygen for this and they can be used in bioreactors to reduce CO2 with hydrogen gas, carbon monoxide or an organic substrate. Gas fermentation using these bacteria has already been realized on an industrial level in two pre-commercial 100,000 gal/yr demonstration facilities to produce fuel ethanol from abundant waste gas resources (by LanzaTech). Acetogens can metabolise a wide variety of substrates that could be used for the production of biocommodities. However, their broad use to produce biofuels and platform chemicals from substrates other than gases or together with gases is hampered by our very limited knowledge about their metabolism and ability to use different substrates simultaneously. Nearly nothing is known about regulatory processes involved in substrate utilization or product formation but this is an absolute requirement for metabolic engineering approaches. The aim of this project is to provide this basic knowledge about metabolic routes in the acetogenic model strain Acetobacterium woodii and their regulation. We will unravel the function of “organelles” found in this bacterium and explore their potential as bio-nanoreactors for the production of biocommodities and pave the road for the industrial use of A. woodii in energy (hydrogen) storage. Thus, this project creates cutting-edge opportunities for the development of biosustainable technologies in Europe.
Summary
Demand for biofuels and other biologically derived commodities is growing worldwide as efforts increase to reduce reliance on fossil fuels and to limit climate change. Most commercial approaches rely on fermentations of organic matter with its inherent problems in producing CO2 and being in conflict with the food supply of humans. These problems are avoided if CO2 can be used as feedstock. Autotrophic organisms can fix CO2 by producing chemicals that are used as building blocks for the synthesis of cellular components (Biomass). Acetate-forming bacteria (acetogens) do neither require light nor oxygen for this and they can be used in bioreactors to reduce CO2 with hydrogen gas, carbon monoxide or an organic substrate. Gas fermentation using these bacteria has already been realized on an industrial level in two pre-commercial 100,000 gal/yr demonstration facilities to produce fuel ethanol from abundant waste gas resources (by LanzaTech). Acetogens can metabolise a wide variety of substrates that could be used for the production of biocommodities. However, their broad use to produce biofuels and platform chemicals from substrates other than gases or together with gases is hampered by our very limited knowledge about their metabolism and ability to use different substrates simultaneously. Nearly nothing is known about regulatory processes involved in substrate utilization or product formation but this is an absolute requirement for metabolic engineering approaches. The aim of this project is to provide this basic knowledge about metabolic routes in the acetogenic model strain Acetobacterium woodii and their regulation. We will unravel the function of “organelles” found in this bacterium and explore their potential as bio-nanoreactors for the production of biocommodities and pave the road for the industrial use of A. woodii in energy (hydrogen) storage. Thus, this project creates cutting-edge opportunities for the development of biosustainable technologies in Europe.
Max ERC Funding
2 497 140 €
Duration
Start date: 2017-10-01, End date: 2022-09-30
Project acronym AdaptoSCOPE
Project Using cis-regulatory mutations to highlight polygenic adaptation in natural plant systems
Researcher (PI) Juliette de Meaux
Host Institution (HI) UNIVERSITAET ZU KOELN
Call Details Consolidator Grant (CoG), LS8, ERC-2014-CoG
Summary The goal of this project is to demonstrate that novel aspects of the molecular basis of Darwinian adaptation can be discovered if the polygenic basis of adaptation is taken into account. This project will use the genome-wide distribution of cis-regulatory variants to discover the molecular pathways that are optimized during adaptation via accumulation of small effect mutations. Current approaches include scans for outlier genes with strong population genetics signatures of selection, or large effect QTL associating with fitness. They can only reveal a small subset of the molecular changes recruited along adaptive paths. Here, instead, the distribution of small effect mutations will be used to make inferences on the targets of polygenic adaptation across divergent populations in each of the two closely related species, A. thaliana and A. lyrata. These species are both found at diverse latitudes and show sign of local adaptation to climatic differences. Mutations affecting cis-regulation will be identified in leaves of plants exposed to various temperature regimes triggering phenotypic responses of adaptive relevance. Their distribution in clusters of functionally connected genes will be quantified. The phylogeographic differences in the distribution of the mutations will be used to disentangle neutral from adaptive clusters of functionally connected genes in each of the two species. This project will identify the molecular pathways subjected collectively to natural selection and provide a completely novel view on adaptive landscapes. It will further examine whether local adaptation occurs by convergent evolution of molecular systems in plants. This approach has the potential to find broad applications in ecology and agriculture.
Summary
The goal of this project is to demonstrate that novel aspects of the molecular basis of Darwinian adaptation can be discovered if the polygenic basis of adaptation is taken into account. This project will use the genome-wide distribution of cis-regulatory variants to discover the molecular pathways that are optimized during adaptation via accumulation of small effect mutations. Current approaches include scans for outlier genes with strong population genetics signatures of selection, or large effect QTL associating with fitness. They can only reveal a small subset of the molecular changes recruited along adaptive paths. Here, instead, the distribution of small effect mutations will be used to make inferences on the targets of polygenic adaptation across divergent populations in each of the two closely related species, A. thaliana and A. lyrata. These species are both found at diverse latitudes and show sign of local adaptation to climatic differences. Mutations affecting cis-regulation will be identified in leaves of plants exposed to various temperature regimes triggering phenotypic responses of adaptive relevance. Their distribution in clusters of functionally connected genes will be quantified. The phylogeographic differences in the distribution of the mutations will be used to disentangle neutral from adaptive clusters of functionally connected genes in each of the two species. This project will identify the molecular pathways subjected collectively to natural selection and provide a completely novel view on adaptive landscapes. It will further examine whether local adaptation occurs by convergent evolution of molecular systems in plants. This approach has the potential to find broad applications in ecology and agriculture.
Max ERC Funding
1 683 120 €
Duration
Start date: 2015-09-01, End date: 2020-08-31
Project acronym AIM2 INFLAMMASOME
Project Cytosolic recognition of foreign nucleic acids: Molecular and functional characterization of AIM2, a central player in DNA-triggered inflammasome activation
Researcher (PI) Veit Hornung
Host Institution (HI) UNIVERSITAETSKLINIKUM BONN
Call Details Starting Grant (StG), LS6, ERC-2009-StG
Summary Host cytokines, chemokines and type I IFNs are critical effectors of the innate immune response to viral and bacterial pathogens. Several classes of germ-line encoded pattern recognition receptors have been identified, which sense non-self nucleic acids and trigger these responses. Recently NLRP-3, a member of the NOD-like receptor (NLR) family, has been shown to sense endogenous danger signals, environmental insults and the DNA viruses adenovirus and HSV. Activation of NLRP-3 induces the formation of a large multiprotein complex in cells termed inflammasome , which controls the activity of pro-caspase-1 and the maturation of pro-IL-1² and pro-IL18 into their active forms. NLRP-3, however, does not regulate these responses to double stranded cytosolic DNA. We identified the cytosolic protein AIM2 as the missing receptor for cytosolic DNA. AIM2 contains a HIN200 domain, which binds to DNA and a pyrin domain, which associates with the adapter molecule ASC to activate both NF-ºB and caspase-1. Knock down of AIM2 down-regulates caspase-1-mediated IL-1² responses following DNA stimulation or vaccinia virus infection. Collectively, these observations demonstrate that AIM2 forms an inflammasome with the DNA ligand and ASC to activate caspase-1. Our underlying hypothesis for this proposal is that AIM2 plays a central role in host-defence to cytosolic microbial pathogens and also in DNA-triggered autoimmunity. The goals of this research proposal are to further characterize the DNA ligand for AIM2, to explore the molecular mechanisms of AIM2 activation, to define the contribution of AIM2 to host-defence against viral and bacterial pathogens and to assess its function in nucleic acid triggered autoimmune disease. The characterization of AIM2 and its role in innate immunity could open new avenues in the advancement of immunotherapy and treatment of autoimmune disease.
Summary
Host cytokines, chemokines and type I IFNs are critical effectors of the innate immune response to viral and bacterial pathogens. Several classes of germ-line encoded pattern recognition receptors have been identified, which sense non-self nucleic acids and trigger these responses. Recently NLRP-3, a member of the NOD-like receptor (NLR) family, has been shown to sense endogenous danger signals, environmental insults and the DNA viruses adenovirus and HSV. Activation of NLRP-3 induces the formation of a large multiprotein complex in cells termed inflammasome , which controls the activity of pro-caspase-1 and the maturation of pro-IL-1² and pro-IL18 into their active forms. NLRP-3, however, does not regulate these responses to double stranded cytosolic DNA. We identified the cytosolic protein AIM2 as the missing receptor for cytosolic DNA. AIM2 contains a HIN200 domain, which binds to DNA and a pyrin domain, which associates with the adapter molecule ASC to activate both NF-ºB and caspase-1. Knock down of AIM2 down-regulates caspase-1-mediated IL-1² responses following DNA stimulation or vaccinia virus infection. Collectively, these observations demonstrate that AIM2 forms an inflammasome with the DNA ligand and ASC to activate caspase-1. Our underlying hypothesis for this proposal is that AIM2 plays a central role in host-defence to cytosolic microbial pathogens and also in DNA-triggered autoimmunity. The goals of this research proposal are to further characterize the DNA ligand for AIM2, to explore the molecular mechanisms of AIM2 activation, to define the contribution of AIM2 to host-defence against viral and bacterial pathogens and to assess its function in nucleic acid triggered autoimmune disease. The characterization of AIM2 and its role in innate immunity could open new avenues in the advancement of immunotherapy and treatment of autoimmune disease.
Max ERC Funding
1 727 920 €
Duration
Start date: 2009-12-01, End date: 2014-11-30
Project acronym AIRSEA
Project Air-Sea Exchanges driven by Light
Researcher (PI) Christian George
Host Institution (HI) CENTRE NATIONAL DE LA RECHERCHE SCIENTIFIQUE CNRS
Call Details Advanced Grant (AdG), PE10, ERC-2011-ADG_20110209
Summary The scientific motivation of this project is the significant presence of organic compounds at the surface of the ocean. They form the link between ocean biogeochemistry through the physico-chemical processes near the water-air interface with primary and secondary aerosol formation and evolution in the air aloft and finally to the climate impact of marine boundary layer aerosols. However, their photochemistry and photosensitizer properties have only been suggested and discussed but never fully addressed because they were beyond reach. This project suggests going significantly beyond this matter of fact by a combination of innovative tools and the development of new ideas.
This project is therefore devoted to new laboratory investigations of processes occurring at the air sea interface to predict emission, formation and evolution of halogenated radicals and aerosols from this vast interface between oceans and atmosphere. It progresses from fundamental laboratory measurements, marine science, surface chemistry, photochemistry … and is therefore interdisciplinary in nature.
It will lead to the development of innovative techniques for characterising chemical processing at the air sea interface (e.g., a multiphase atmospheric simulation chamber, a time-resolved fluorescence technique for characterising chemical processing at the air-sea interface). It will allow the assessment of new emerging ideas such as a quantitative description of the importance of photosensitized reactions in the visible at the air/sea interface as a major source of halogenated radicals and aerosols in the marine environment.
This new understanding will impact on our ability to describe atmospheric chemistry in the marine environment which has strong impact on the urban air quality of coastal regions (which by the way represent highly populated regions ) but also on climate change by providing new input for global climate models.
Summary
The scientific motivation of this project is the significant presence of organic compounds at the surface of the ocean. They form the link between ocean biogeochemistry through the physico-chemical processes near the water-air interface with primary and secondary aerosol formation and evolution in the air aloft and finally to the climate impact of marine boundary layer aerosols. However, their photochemistry and photosensitizer properties have only been suggested and discussed but never fully addressed because they were beyond reach. This project suggests going significantly beyond this matter of fact by a combination of innovative tools and the development of new ideas.
This project is therefore devoted to new laboratory investigations of processes occurring at the air sea interface to predict emission, formation and evolution of halogenated radicals and aerosols from this vast interface between oceans and atmosphere. It progresses from fundamental laboratory measurements, marine science, surface chemistry, photochemistry … and is therefore interdisciplinary in nature.
It will lead to the development of innovative techniques for characterising chemical processing at the air sea interface (e.g., a multiphase atmospheric simulation chamber, a time-resolved fluorescence technique for characterising chemical processing at the air-sea interface). It will allow the assessment of new emerging ideas such as a quantitative description of the importance of photosensitized reactions in the visible at the air/sea interface as a major source of halogenated radicals and aerosols in the marine environment.
This new understanding will impact on our ability to describe atmospheric chemistry in the marine environment which has strong impact on the urban air quality of coastal regions (which by the way represent highly populated regions ) but also on climate change by providing new input for global climate models.
Max ERC Funding
2 366 276 €
Duration
Start date: 2012-04-01, End date: 2017-03-31
