Project acronym 100 Archaic Genomes
Project Genome sequences from extinct hominins
Researcher (PI) Svante PÄÄBO
Host Institution (HI) MAX-PLANCK-GESELLSCHAFT ZUR FORDERUNG DER WISSENSCHAFTEN EV
Call Details Advanced Grant (AdG), LS2, ERC-2015-AdG
Summary Neandertals and Denisovans, an Asian group distantly related to Neandertals, are the closest evolutionary relatives of present-day humans. They are thus of direct relevance for understanding the origin of modern humans and how modern humans differ from their closest relatives. We will generate genome-wide data from a large number of Neandertal and Denisovan individuals from across their geographical and temporal range as well as from other extinct hominin groups which we may discover. This will be possible by automating highly sensitive approaches to ancient DNA extraction and DNA libraries construction that we have developed so that they can be applied to many specimens from many sites in order to identify those that contain retrievable DNA. Whenever possible we will sequence whole genomes and in other cases use DNA capture methods to generate high-quality data from representative parts of the genome. This will allow us to study the population history of Neandertals and Denisovans, elucidate how many times and where these extinct hominins contributed genes to present-day people, and the extent to which modern humans and archaic groups contributed genetically to Neandertals and Denisovans. By retrieving DNA from specimens that go back to the Middle Pleistocene we will furthermore shed light on the early history and origins of Neandertals and Denisovans.
Summary
Neandertals and Denisovans, an Asian group distantly related to Neandertals, are the closest evolutionary relatives of present-day humans. They are thus of direct relevance for understanding the origin of modern humans and how modern humans differ from their closest relatives. We will generate genome-wide data from a large number of Neandertal and Denisovan individuals from across their geographical and temporal range as well as from other extinct hominin groups which we may discover. This will be possible by automating highly sensitive approaches to ancient DNA extraction and DNA libraries construction that we have developed so that they can be applied to many specimens from many sites in order to identify those that contain retrievable DNA. Whenever possible we will sequence whole genomes and in other cases use DNA capture methods to generate high-quality data from representative parts of the genome. This will allow us to study the population history of Neandertals and Denisovans, elucidate how many times and where these extinct hominins contributed genes to present-day people, and the extent to which modern humans and archaic groups contributed genetically to Neandertals and Denisovans. By retrieving DNA from specimens that go back to the Middle Pleistocene we will furthermore shed light on the early history and origins of Neandertals and Denisovans.
Max ERC Funding
2 350 000 €
Duration
Start date: 2016-11-01, End date: 2021-10-31
Project acronym 2-HIT
Project Genetic interaction networks: From C. elegans to human disease
Researcher (PI) Ben Lehner
Host Institution (HI) FUNDACIO CENTRE DE REGULACIO GENOMICA
Call Details Starting Grant (StG), LS2, ERC-2007-StG
Summary Most hereditary diseases in humans are genetically complex, resulting from combinations of mutations in multiple genes. However synthetic interactions between genes are very difficult to identify in population studies because of a lack of statistical power and we fundamentally do not understand how mutations interact to produce phenotypes. C. elegans is a unique animal in which genetic interactions can be rapidly identified in vivo using RNA interference, and we recently used this system to construct the first genetic interaction network for any animal, focused on signal transduction genes. The first objective of this proposal is to extend this work and map a comprehensive genetic interaction network for this model metazoan. This project will provide the first insights into the global properties of animal genetic interaction networks, and a comprehensive view of the functional relationships between genes in an animal. The second objective of the proposal is to use C. elegans to develop and validate experimentally integrated gene networks that connect genes to phenotypes and predict genetic interactions on a genome-wide scale. The methods that we develop and validate in C. elegans will then be applied to predict phenotypes and interactions for human genes. The final objective is to dissect the molecular mechanisms underlying genetic interactions, and to understand how these interactions evolve. The combined aim of these three objectives is to generate a framework for understanding and predicting how mutations interact to produce phenotypes, including in human disease.
Summary
Most hereditary diseases in humans are genetically complex, resulting from combinations of mutations in multiple genes. However synthetic interactions between genes are very difficult to identify in population studies because of a lack of statistical power and we fundamentally do not understand how mutations interact to produce phenotypes. C. elegans is a unique animal in which genetic interactions can be rapidly identified in vivo using RNA interference, and we recently used this system to construct the first genetic interaction network for any animal, focused on signal transduction genes. The first objective of this proposal is to extend this work and map a comprehensive genetic interaction network for this model metazoan. This project will provide the first insights into the global properties of animal genetic interaction networks, and a comprehensive view of the functional relationships between genes in an animal. The second objective of the proposal is to use C. elegans to develop and validate experimentally integrated gene networks that connect genes to phenotypes and predict genetic interactions on a genome-wide scale. The methods that we develop and validate in C. elegans will then be applied to predict phenotypes and interactions for human genes. The final objective is to dissect the molecular mechanisms underlying genetic interactions, and to understand how these interactions evolve. The combined aim of these three objectives is to generate a framework for understanding and predicting how mutations interact to produce phenotypes, including in human disease.
Max ERC Funding
1 100 000 €
Duration
Start date: 2008-09-01, End date: 2014-04-30
Project acronym 2D4D
Project Disruptive Digitalization for Decarbonization
Researcher (PI) Elena Verdolini
Host Institution (HI) UNIVERSITA DEGLI STUDI DI BRESCIA
Call Details Starting Grant (StG), SH2, ERC-2019-STG
Summary By 2040, all major sectors of the European economy will be deeply digitalized. By then, the EU aims at reducing greenhouse gas emissions by 60% with respect to 1990 levels. Digitalization will affect decarbonization efforts because of its impacts on energy demand, employment, competitiveness, trade patterns and its distributional, behavioural and ethical implications. Yet, the policy debates around these two transformations are largely disjoint.
The aim of the 2D4D project is ensure that the digital revolution acts as an enabler – and not as a barrier – for decarbonization. The project quantifies the decarbonization implications of three disruptive digitalization technologies in hard-to-decarbonize sectors: (1) Additive Manufacturing in industry, (2) Mobility-as-a-Service in transportation, and (3) Artificial Intelligence in buildings.
The first objective of 2D4D is to generate a one-of-a-kind data collection to investigate the technical and socio-economic dynamics of these technologies, and how they may affect decarbonization narratives and scenarios. This will be achieved through several data collection methods, including desk research, surveys and expert elicitations.
The second objective of 2D4D is to include digitalization dynamics in decarbonization narratives and pathways. On the one hand, this entails enhancing decarbonization narratives (specifically, the Shared Socio-economic Pathways) to describe digitalization dynamics. On the other hand, it requires improving the representation of sector-specific digitalization dynamics in Integrated Assessment Models, one of the main tools available to generate decarbonization pathways.
The third objective of 2D4D is to identify no-regret, robust policy portfolios. These will be designed to ensure that digitalization unfolds in an inclusive, climate-beneficial way, and that decarbonization policies capitalize on digital technologies to support the energy transition.
Summary
By 2040, all major sectors of the European economy will be deeply digitalized. By then, the EU aims at reducing greenhouse gas emissions by 60% with respect to 1990 levels. Digitalization will affect decarbonization efforts because of its impacts on energy demand, employment, competitiveness, trade patterns and its distributional, behavioural and ethical implications. Yet, the policy debates around these two transformations are largely disjoint.
The aim of the 2D4D project is ensure that the digital revolution acts as an enabler – and not as a barrier – for decarbonization. The project quantifies the decarbonization implications of three disruptive digitalization technologies in hard-to-decarbonize sectors: (1) Additive Manufacturing in industry, (2) Mobility-as-a-Service in transportation, and (3) Artificial Intelligence in buildings.
The first objective of 2D4D is to generate a one-of-a-kind data collection to investigate the technical and socio-economic dynamics of these technologies, and how they may affect decarbonization narratives and scenarios. This will be achieved through several data collection methods, including desk research, surveys and expert elicitations.
The second objective of 2D4D is to include digitalization dynamics in decarbonization narratives and pathways. On the one hand, this entails enhancing decarbonization narratives (specifically, the Shared Socio-economic Pathways) to describe digitalization dynamics. On the other hand, it requires improving the representation of sector-specific digitalization dynamics in Integrated Assessment Models, one of the main tools available to generate decarbonization pathways.
The third objective of 2D4D is to identify no-regret, robust policy portfolios. These will be designed to ensure that digitalization unfolds in an inclusive, climate-beneficial way, and that decarbonization policies capitalize on digital technologies to support the energy transition.
Max ERC Funding
1 498 375 €
Duration
Start date: 2020-10-01, End date: 2025-09-30
Project acronym 3D-loop
Project Mechanism of homology search and the logic of homologous chromosome pairing in meiosis
Researcher (PI) Aurele PIAZZA
Host Institution (HI) CENTRE NATIONAL DE LA RECHERCHE SCIENTIFIQUE CNRS
Call Details Starting Grant (StG), LS2, ERC-2019-STG
Summary Homologous recombination (HR) is a conserved DNA double-strand breaks (DSB) repair pathway that uniquely uses an intact DNA molecule as a template. Genome-wide homology search is carried out by a nucleoprotein filament (NPF) assembled on the ssDNA flanking the DSB, and whose product is a “D-loop” joint molecule. Beyond accurate DSB repair, this capacity of HR to spatially associates homologous molecules is also harnessed for homolog pairing in meiosis. The goal of “3D-loop” is to tackle two long lasting conundrums: the fundamental homology search mechanism that achieves accurate and efficient identification of a single homologous donor in the vastness of the genome and nucleus, and how this mechanism is adapted for the purpose of homologs attachment in meiosis.
I overcame the main hurdle to study these core steps of HR by developing a suite of proximity ligation-based methodologies and experimental systems to physically detect joint molecules in yeast cells. It revealed elaborate regulation controlling D-loop dynamics and a novel class of joint molecules. This proposal builds upon these methodologies and findings to first address basic properties of the homology sampling process by the NPF and the role of D-loop dynamics, with the long-term goal to establish a quantitative framework of homology search in mitotic cells (WP1). Second, the meiosis-specific regulation of homology search leading to homolog pairing likely integrates chromosomal-scale information. Genome re-synthesis and engineering approaches will be deployed to (i) achieve a quantitative and dynamic cartography of the cytological and molecular events of meiosis over a large chromosomal region, (ii) probe cis-acting regulations at the chromosomal scale, and (iii) revisit the molecular paradigm for crossover formation (WP2). We expect this project to shed light on the fundamental process of homology search and its involvement in the chromosome pairing phenomenon lying at the basis of sexual reproduction.
Summary
Homologous recombination (HR) is a conserved DNA double-strand breaks (DSB) repair pathway that uniquely uses an intact DNA molecule as a template. Genome-wide homology search is carried out by a nucleoprotein filament (NPF) assembled on the ssDNA flanking the DSB, and whose product is a “D-loop” joint molecule. Beyond accurate DSB repair, this capacity of HR to spatially associates homologous molecules is also harnessed for homolog pairing in meiosis. The goal of “3D-loop” is to tackle two long lasting conundrums: the fundamental homology search mechanism that achieves accurate and efficient identification of a single homologous donor in the vastness of the genome and nucleus, and how this mechanism is adapted for the purpose of homologs attachment in meiosis.
I overcame the main hurdle to study these core steps of HR by developing a suite of proximity ligation-based methodologies and experimental systems to physically detect joint molecules in yeast cells. It revealed elaborate regulation controlling D-loop dynamics and a novel class of joint molecules. This proposal builds upon these methodologies and findings to first address basic properties of the homology sampling process by the NPF and the role of D-loop dynamics, with the long-term goal to establish a quantitative framework of homology search in mitotic cells (WP1). Second, the meiosis-specific regulation of homology search leading to homolog pairing likely integrates chromosomal-scale information. Genome re-synthesis and engineering approaches will be deployed to (i) achieve a quantitative and dynamic cartography of the cytological and molecular events of meiosis over a large chromosomal region, (ii) probe cis-acting regulations at the chromosomal scale, and (iii) revisit the molecular paradigm for crossover formation (WP2). We expect this project to shed light on the fundamental process of homology search and its involvement in the chromosome pairing phenomenon lying at the basis of sexual reproduction.
Max ERC Funding
1 499 779 €
Duration
Start date: 2020-01-01, End date: 2024-12-31
Project acronym 3D-REPAIR
Project Spatial organization of DNA repair within the nucleus
Researcher (PI) Evanthia Soutoglou
Host Institution (HI) THE UNIVERSITY OF SUSSEX
Call Details Consolidator Grant (CoG), LS2, ERC-2015-CoG
Summary Faithful repair of double stranded DNA breaks (DSBs) is essential, as they are at the origin of genome instability, chromosomal translocations and cancer. Cells repair DSBs through different pathways, which can be faithful or mutagenic, and the balance between them at a given locus must be tightly regulated to preserve genome integrity. Although, much is known about DSB repair factors, how the choice between pathways is controlled within the nuclear environment is not understood. We have shown that nuclear architecture and non-random genome organization determine the frequency of chromosomal translocations and that pathway choice is dictated by the spatial organization of DNA in the nucleus. Nevertheless, what determines which pathway is activated in response to DSBs at specific genomic locations is not understood. Furthermore, the impact of 3D-genome folding on the kinetics and efficiency of DSB repair is completely unknown.
Here we aim to understand how nuclear compartmentalization, chromatin structure and genome organization impact on the efficiency of detection, signaling and repair of DSBs. We will unravel what determines the DNA repair specificity within distinct nuclear compartments using protein tethering, promiscuous biotinylation and quantitative proteomics. We will determine how DNA repair is orchestrated at different heterochromatin structures using a CRISPR/Cas9-based system that allows, for the first time robust induction of DSBs at specific heterochromatin compartments. Finally, we will investigate the role of 3D-genome folding in the kinetics of DNA repair and pathway choice using single nucleotide resolution DSB-mapping coupled to 3D-topological maps.
This proposal has significant implications for understanding the mechanisms controlling DNA repair within the nuclear environment and will reveal the regions of the genome that are susceptible to genomic instability and help us understand why certain mutations and translocations are recurrent in cancer
Summary
Faithful repair of double stranded DNA breaks (DSBs) is essential, as they are at the origin of genome instability, chromosomal translocations and cancer. Cells repair DSBs through different pathways, which can be faithful or mutagenic, and the balance between them at a given locus must be tightly regulated to preserve genome integrity. Although, much is known about DSB repair factors, how the choice between pathways is controlled within the nuclear environment is not understood. We have shown that nuclear architecture and non-random genome organization determine the frequency of chromosomal translocations and that pathway choice is dictated by the spatial organization of DNA in the nucleus. Nevertheless, what determines which pathway is activated in response to DSBs at specific genomic locations is not understood. Furthermore, the impact of 3D-genome folding on the kinetics and efficiency of DSB repair is completely unknown.
Here we aim to understand how nuclear compartmentalization, chromatin structure and genome organization impact on the efficiency of detection, signaling and repair of DSBs. We will unravel what determines the DNA repair specificity within distinct nuclear compartments using protein tethering, promiscuous biotinylation and quantitative proteomics. We will determine how DNA repair is orchestrated at different heterochromatin structures using a CRISPR/Cas9-based system that allows, for the first time robust induction of DSBs at specific heterochromatin compartments. Finally, we will investigate the role of 3D-genome folding in the kinetics of DNA repair and pathway choice using single nucleotide resolution DSB-mapping coupled to 3D-topological maps.
This proposal has significant implications for understanding the mechanisms controlling DNA repair within the nuclear environment and will reveal the regions of the genome that are susceptible to genomic instability and help us understand why certain mutations and translocations are recurrent in cancer
Max ERC Funding
1 999 750 €
Duration
Start date: 2017-03-01, End date: 2022-02-28
Project acronym 3DEpi
Project Transgenerational epigenetic inheritance of chromatin states : the role of Polycomb and 3D chromosome architecture
Researcher (PI) Giacomo CAVALLI
Host Institution (HI) CENTRE NATIONAL DE LA RECHERCHE SCIENTIFIQUE CNRS
Call Details Advanced Grant (AdG), LS2, ERC-2017-ADG
Summary Epigenetic inheritance entails transmission of phenotypic traits not encoded in the DNA sequence and, in the most extreme case, Transgenerational Epigenetic Inheritance (TEI) involves transmission of memory through multiple generations. Very little is known on the mechanisms governing TEI and this is the subject of the present proposal. By transiently enhancing long-range chromatin interactions, we recently established isogenic Drosophila epilines that carry stable alternative epialleles, defined by differential levels of the Polycomb-dependent H3K27me3 mark. Furthermore, we extended our paradigm to natural phenotypes. These are ideal systems to study the role of Polycomb group (PcG) proteins and other components in regulating nuclear organization and epigenetic inheritance of chromatin states. The present project conjugates genetics, epigenomics, imaging and molecular biology to reach three critical aims.
Aim 1: Analysis of the molecular mechanisms regulating Polycomb-mediated TEI. We will identify the DNA, protein and RNA components that trigger and maintain transgenerational chromatin inheritance as well as their mechanisms of action.
Aim 2: Role of 3D genome organization in the regulation of TEI. We will analyze the developmental dynamics of TEI-inducing long-range chromatin interactions, identify chromatin components mediating 3D chromatin contacts and characterize their function in the TEI process.
Aim 3: Identification of a broader role of TEI during development. TEI might reflect a normal role of PcG components in the transmission of parental chromatin onto the next embryonic generation. We will explore this possibility by establishing other TEI paradigms and by relating TEI to the normal PcG function in these systems and in normal development.
This research program will unravel the biological significance and the molecular underpinnings of TEI and lead the way towards establishing this area of research into a consolidated scientific discipline.
Summary
Epigenetic inheritance entails transmission of phenotypic traits not encoded in the DNA sequence and, in the most extreme case, Transgenerational Epigenetic Inheritance (TEI) involves transmission of memory through multiple generations. Very little is known on the mechanisms governing TEI and this is the subject of the present proposal. By transiently enhancing long-range chromatin interactions, we recently established isogenic Drosophila epilines that carry stable alternative epialleles, defined by differential levels of the Polycomb-dependent H3K27me3 mark. Furthermore, we extended our paradigm to natural phenotypes. These are ideal systems to study the role of Polycomb group (PcG) proteins and other components in regulating nuclear organization and epigenetic inheritance of chromatin states. The present project conjugates genetics, epigenomics, imaging and molecular biology to reach three critical aims.
Aim 1: Analysis of the molecular mechanisms regulating Polycomb-mediated TEI. We will identify the DNA, protein and RNA components that trigger and maintain transgenerational chromatin inheritance as well as their mechanisms of action.
Aim 2: Role of 3D genome organization in the regulation of TEI. We will analyze the developmental dynamics of TEI-inducing long-range chromatin interactions, identify chromatin components mediating 3D chromatin contacts and characterize their function in the TEI process.
Aim 3: Identification of a broader role of TEI during development. TEI might reflect a normal role of PcG components in the transmission of parental chromatin onto the next embryonic generation. We will explore this possibility by establishing other TEI paradigms and by relating TEI to the normal PcG function in these systems and in normal development.
This research program will unravel the biological significance and the molecular underpinnings of TEI and lead the way towards establishing this area of research into a consolidated scientific discipline.
Max ERC Funding
2 500 000 €
Duration
Start date: 2018-11-01, End date: 2023-10-31
Project acronym 4C
Project 4C technology: uncovering the multi-dimensional structure of the genome
Researcher (PI) Wouter Leonard De Laat
Host Institution (HI) KONINKLIJKE NEDERLANDSE AKADEMIE VAN WETENSCHAPPEN - KNAW
Call Details Starting Grant (StG), LS2, ERC-2007-StG
Summary The architecture of DNA in the cell nucleus is an emerging epigenetic key contributor to genome function. We recently developed 4C technology, a high-throughput technique that combines state-of-the-art 3C technology with tailored micro-arrays to uniquely allow for an unbiased genome-wide search for DNA loci that interact in the nuclear space. Based on 4C technology, we were the first to provide a comprehensive overview of long-range DNA contacts of selected loci. The data showed that active and inactive chromatin domains contact many distinct regions within and between chromosomes and genes switch long-range DNA contacts in relation to their expression status. 4C technology not only allows investigating the three-dimensional structure of DNA in the nucleus, it also accurately reconstructs at least 10 megabases of the one-dimensional chromosome sequence map around the target sequence. Changes in this physical map as a result of genomic rearrangements are therefore identified by 4C technology. We recently demonstrated that 4C detects deletions, balanced inversions and translocations in patient samples at a resolution (~7kb) that allowed immediate sequencing of the breakpoints. Excitingly, 4C technology therefore offers the first high-resolution genomic approach that can identify both balanced and unbalanced genomic rearrangements. 4C is expected to become an important tool in clinical diagnosis and prognosis. Key objectives of this proposal are: 1. Explore the functional significance of DNA folding in the nucleus by systematically applying 4C technology to differentially expressed gene loci. 2. Adapt 4C technology such that it allows for massive parallel analysis of DNA interactions between regulatory elements and gene promoters. This method would greatly facilitate the identification of functionally relevant DNA elements in the genome. 3. Develop 4C technology into a clinical diagnostic tool for the accurate detection of balanced and unbalanced rearrangements.
Summary
The architecture of DNA in the cell nucleus is an emerging epigenetic key contributor to genome function. We recently developed 4C technology, a high-throughput technique that combines state-of-the-art 3C technology with tailored micro-arrays to uniquely allow for an unbiased genome-wide search for DNA loci that interact in the nuclear space. Based on 4C technology, we were the first to provide a comprehensive overview of long-range DNA contacts of selected loci. The data showed that active and inactive chromatin domains contact many distinct regions within and between chromosomes and genes switch long-range DNA contacts in relation to their expression status. 4C technology not only allows investigating the three-dimensional structure of DNA in the nucleus, it also accurately reconstructs at least 10 megabases of the one-dimensional chromosome sequence map around the target sequence. Changes in this physical map as a result of genomic rearrangements are therefore identified by 4C technology. We recently demonstrated that 4C detects deletions, balanced inversions and translocations in patient samples at a resolution (~7kb) that allowed immediate sequencing of the breakpoints. Excitingly, 4C technology therefore offers the first high-resolution genomic approach that can identify both balanced and unbalanced genomic rearrangements. 4C is expected to become an important tool in clinical diagnosis and prognosis. Key objectives of this proposal are: 1. Explore the functional significance of DNA folding in the nucleus by systematically applying 4C technology to differentially expressed gene loci. 2. Adapt 4C technology such that it allows for massive parallel analysis of DNA interactions between regulatory elements and gene promoters. This method would greatly facilitate the identification of functionally relevant DNA elements in the genome. 3. Develop 4C technology into a clinical diagnostic tool for the accurate detection of balanced and unbalanced rearrangements.
Max ERC Funding
1 225 000 €
Duration
Start date: 2008-09-01, End date: 2013-08-31
Project acronym 4D-GenEx
Project Spatio-temporal Organization and Expression of the Genome
Researcher (PI) Antoine COULON
Host Institution (HI) CENTRE NATIONAL DE LA RECHERCHE SCIENTIFIQUE CNRS
Call Details Starting Grant (StG), LS2, ERC-2017-STG
Summary This project investigates the two-way relationship between spatio-temporal genome organization and coordinated gene regulation, through an approach at the interface between physics, computer science and biology.
In the nucleus, preferred positions are observed from chromosomes to single genes, in relation to normal and pathological cellular states. Evidence indicates a complex spatio-temporal coupling between co-regulated genes: e.g. certain genes cluster spatially when responding to similar factors and transcriptional noise patterns suggest domain-wide mechanisms. Yet, no individual experiment allows probing transcriptional coordination in 4 dimensions (FISH, live locus tracking, Hi-C...). Interpreting such data also critically requires theory (stochastic processes, statistical physics…). A lack of appropriate experimental/analytical approaches is impairing our understanding of the 4D genome.
Our proposal combines cutting-edge single-molecule imaging, signal-theory data analysis and physical modeling to study how genes coordinate in space and time in a single nucleus. Our objectives are to understand (a) competition/recycling of shared resources between genes within subnuclear compartments, (b) how enhancers communicate with genes domain-wide, and (c) the role of local conformational dynamics and supercoiling in gene co-regulation. Our organizing hypothesis is that, by acting on their microenvironment, genes shape their co-expression with other genes.
Building upon my expertise, we will use dual-color MS2/PP7 RNA labeling to visualize for the first time transcription and motion of pairs of hormone-responsive genes in real time. With our innovative signal analysis tools, we will extract spatio-temporal signatures of underlying processes, which we will investigate with stochastic modeling and validate through experimental perturbations. We expect to uncover how the functional organization of the linear genome relates to its physical properties and dynamics in 4D.
Summary
This project investigates the two-way relationship between spatio-temporal genome organization and coordinated gene regulation, through an approach at the interface between physics, computer science and biology.
In the nucleus, preferred positions are observed from chromosomes to single genes, in relation to normal and pathological cellular states. Evidence indicates a complex spatio-temporal coupling between co-regulated genes: e.g. certain genes cluster spatially when responding to similar factors and transcriptional noise patterns suggest domain-wide mechanisms. Yet, no individual experiment allows probing transcriptional coordination in 4 dimensions (FISH, live locus tracking, Hi-C...). Interpreting such data also critically requires theory (stochastic processes, statistical physics…). A lack of appropriate experimental/analytical approaches is impairing our understanding of the 4D genome.
Our proposal combines cutting-edge single-molecule imaging, signal-theory data analysis and physical modeling to study how genes coordinate in space and time in a single nucleus. Our objectives are to understand (a) competition/recycling of shared resources between genes within subnuclear compartments, (b) how enhancers communicate with genes domain-wide, and (c) the role of local conformational dynamics and supercoiling in gene co-regulation. Our organizing hypothesis is that, by acting on their microenvironment, genes shape their co-expression with other genes.
Building upon my expertise, we will use dual-color MS2/PP7 RNA labeling to visualize for the first time transcription and motion of pairs of hormone-responsive genes in real time. With our innovative signal analysis tools, we will extract spatio-temporal signatures of underlying processes, which we will investigate with stochastic modeling and validate through experimental perturbations. We expect to uncover how the functional organization of the linear genome relates to its physical properties and dynamics in 4D.
Max ERC Funding
1 499 750 €
Duration
Start date: 2018-04-01, End date: 2023-03-31
Project acronym ACCOMPLI
Project Assembly and maintenance of a co-regulated chromosomal compartment
Researcher (PI) Peter Burkhard Becker
Host Institution (HI) LUDWIG-MAXIMILIANS-UNIVERSITAET MUENCHEN
Call Details Advanced Grant (AdG), LS2, ERC-2011-ADG_20110310
Summary "Eukaryotic nuclei are organised into functional compartments, – local microenvironments that are enriched in certain molecules or biochemical activities and therefore specify localised functional outputs. Our study seeks to unveil fundamental principles of co-regulation of genes in a chromo¬somal compartment and the preconditions for homeostasis of such a compartment in the dynamic nuclear environment.
The dosage-compensated X chromosome of male Drosophila flies satisfies the criteria for a functional com¬partment. It is rendered structurally distinct from all other chromosomes by association of a regulatory ribonucleoprotein ‘Dosage Compensation Complex’ (DCC), enrichment of histone modifications and global decondensation. As a result, most genes on the X chromosome are co-ordinately activated. Autosomal genes inserted into the X acquire X-chromosomal features and are subject to the X-specific regulation.
We seek to uncover the molecular principles that initiate, establish and maintain the dosage-compensated chromosome. We will follow the kinetics of DCC assembly and the timing of association with different types of chromosomal targets in nuclei with high spatial resolution afforded by sub-wavelength microscopy and deep sequencing of DNA binding sites. We will characterise DCC sub-complexes with respect to their roles as kinetic assembly intermediates or as representations of local, functional heterogeneity. We will evaluate the roles of a DCC- novel ubiquitin ligase activity for homeostasis.
Crucial to the recruitment of the DCC and its distribution to target genes are non-coding roX RNAs that are transcribed from the X. We will determine the secondary structure ‘signatures’ of roX RNAs in vitro and determine the binding sites of the protein subunits in vivo. By biochemical and cellular reconstitution will test the hypothesis that roX-encoded RNA aptamers orchestrate the assembly of the DCC and contribute to the exquisite targeting of the complex."
Summary
"Eukaryotic nuclei are organised into functional compartments, – local microenvironments that are enriched in certain molecules or biochemical activities and therefore specify localised functional outputs. Our study seeks to unveil fundamental principles of co-regulation of genes in a chromo¬somal compartment and the preconditions for homeostasis of such a compartment in the dynamic nuclear environment.
The dosage-compensated X chromosome of male Drosophila flies satisfies the criteria for a functional com¬partment. It is rendered structurally distinct from all other chromosomes by association of a regulatory ribonucleoprotein ‘Dosage Compensation Complex’ (DCC), enrichment of histone modifications and global decondensation. As a result, most genes on the X chromosome are co-ordinately activated. Autosomal genes inserted into the X acquire X-chromosomal features and are subject to the X-specific regulation.
We seek to uncover the molecular principles that initiate, establish and maintain the dosage-compensated chromosome. We will follow the kinetics of DCC assembly and the timing of association with different types of chromosomal targets in nuclei with high spatial resolution afforded by sub-wavelength microscopy and deep sequencing of DNA binding sites. We will characterise DCC sub-complexes with respect to their roles as kinetic assembly intermediates or as representations of local, functional heterogeneity. We will evaluate the roles of a DCC- novel ubiquitin ligase activity for homeostasis.
Crucial to the recruitment of the DCC and its distribution to target genes are non-coding roX RNAs that are transcribed from the X. We will determine the secondary structure ‘signatures’ of roX RNAs in vitro and determine the binding sites of the protein subunits in vivo. By biochemical and cellular reconstitution will test the hypothesis that roX-encoded RNA aptamers orchestrate the assembly of the DCC and contribute to the exquisite targeting of the complex."
Max ERC Funding
2 482 770 €
Duration
Start date: 2012-02-01, End date: 2017-01-31
Project acronym ACCUPOL
Project Unlimited Growth? A Comparative Analysis of Causes and Consequences of Policy Accumulation
Researcher (PI) Christoph KNILL
Host Institution (HI) LUDWIG-MAXIMILIANS-UNIVERSITAET MUENCHEN
Call Details Advanced Grant (AdG), SH2, ERC-2017-ADG
Summary ACCUPOL systematically analyzes an intuitively well-known, but curiously under-researched phenomenon: policy accumulation. Societal modernization and progress bring about a continuously growing pile of policies in most political systems. At the same time, however, the administrative capacities for implementation are largely stagnant. While being societally desirable in principle, ever-more policies hence may potentially imply less in terms of policy achievements. Whether or not policy accumulation remains at a ‘sustainable’ rate thus crucially affects the long-term output legitimacy of modern democracies.
Given this development, the central focus of ACCUPOL lies on three questions: Do accumulation rates vary across countries and policy sectors? Which factors mitigate policy accumulation? And to what extent is policy accumulation really associated with an increasing prevalence of implementation deficits? In answering these questions, ACCUPOL radically departs from established research traditions in public policy.
First, the project develops new analytical concepts: Rather than relying on individual policy change as the unit of analysis, we consider policy accumulation to assess the growth of policy portfolios over time. In terms of implementation, ACCUPOL takes into account the overall prevalence of implementation deficits in a given sector instead of analyzing the effectiveness of individual implementation processes.
Second, this analytical innovation also implies a paradigmatic theoretical shift. Because existing theories focus on the analysis of individual policies, they are of limited help to understand causes and consequences of policy accumulation. ACCUPOL develops a novel theoretical approach to fill this theoretical gap.
Third, the project provides new empirical evidence on the prevalence of policy accumulation and implementation deficits focusing on 25 OECD countries and two key policy areas (social and environmental policy).
Summary
ACCUPOL systematically analyzes an intuitively well-known, but curiously under-researched phenomenon: policy accumulation. Societal modernization and progress bring about a continuously growing pile of policies in most political systems. At the same time, however, the administrative capacities for implementation are largely stagnant. While being societally desirable in principle, ever-more policies hence may potentially imply less in terms of policy achievements. Whether or not policy accumulation remains at a ‘sustainable’ rate thus crucially affects the long-term output legitimacy of modern democracies.
Given this development, the central focus of ACCUPOL lies on three questions: Do accumulation rates vary across countries and policy sectors? Which factors mitigate policy accumulation? And to what extent is policy accumulation really associated with an increasing prevalence of implementation deficits? In answering these questions, ACCUPOL radically departs from established research traditions in public policy.
First, the project develops new analytical concepts: Rather than relying on individual policy change as the unit of analysis, we consider policy accumulation to assess the growth of policy portfolios over time. In terms of implementation, ACCUPOL takes into account the overall prevalence of implementation deficits in a given sector instead of analyzing the effectiveness of individual implementation processes.
Second, this analytical innovation also implies a paradigmatic theoretical shift. Because existing theories focus on the analysis of individual policies, they are of limited help to understand causes and consequences of policy accumulation. ACCUPOL develops a novel theoretical approach to fill this theoretical gap.
Third, the project provides new empirical evidence on the prevalence of policy accumulation and implementation deficits focusing on 25 OECD countries and two key policy areas (social and environmental policy).
Max ERC Funding
2 359 000 €
Duration
Start date: 2018-10-01, End date: 2023-09-30