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 3DCellPhase-
Project In situ Structural Analysis of Molecular Crowding and Phase Separation
Researcher (PI) Julia MAHAMID
Host Institution (HI) EUROPEAN MOLECULAR BIOLOGY LABORATORY
Call Details Starting Grant (StG), LS1, ERC-2017-STG
Summary This proposal brings together two fields in biology, namely the emerging field of phase-separated assemblies in cell biology and state-of-the-art cellular cryo-electron tomography, to advance our understanding on a fundamental, yet illusive, question: the molecular organization of the cytoplasm.
Eukaryotes organize their biochemical reactions into functionally distinct compartments. Intriguingly, many, if not most, cellular compartments are not membrane enclosed. Rather, they assemble dynamically by phase separation, typically triggered upon a specific event. Despite significant progress on reconstituting such liquid-like assemblies in vitro, we lack information as to whether these compartments in vivo are indeed amorphous liquids, or whether they exhibit structural features such as gels or fibers. My recent work on sample preparation of cells for cryo-electron tomography, including cryo-focused ion beam thinning, guided by 3D correlative fluorescence microscopy, shows that we can now prepare site-specific ‘electron-transparent windows’ in suitable eukaryotic systems, which allow direct examination of structural features of cellular compartments in their cellular context. Here, we will use these techniques to elucidate the structural principles and cytoplasmic environment driving the dynamic assembly of two phase-separated compartments: Stress granules, which are RNA bodies that form rapidly in the cytoplasm upon cellular stress, and centrosomes, which are sites of microtubule nucleation. We will combine these studies with a quantitative description of the crowded nature of cytoplasm and of its local variations, to provide a direct readout of the impact of excluded volume on molecular assembly in living cells. Taken together, these studies will provide fundamental insights into the structural basis by which cells form biochemical compartments.
Summary
This proposal brings together two fields in biology, namely the emerging field of phase-separated assemblies in cell biology and state-of-the-art cellular cryo-electron tomography, to advance our understanding on a fundamental, yet illusive, question: the molecular organization of the cytoplasm.
Eukaryotes organize their biochemical reactions into functionally distinct compartments. Intriguingly, many, if not most, cellular compartments are not membrane enclosed. Rather, they assemble dynamically by phase separation, typically triggered upon a specific event. Despite significant progress on reconstituting such liquid-like assemblies in vitro, we lack information as to whether these compartments in vivo are indeed amorphous liquids, or whether they exhibit structural features such as gels or fibers. My recent work on sample preparation of cells for cryo-electron tomography, including cryo-focused ion beam thinning, guided by 3D correlative fluorescence microscopy, shows that we can now prepare site-specific ‘electron-transparent windows’ in suitable eukaryotic systems, which allow direct examination of structural features of cellular compartments in their cellular context. Here, we will use these techniques to elucidate the structural principles and cytoplasmic environment driving the dynamic assembly of two phase-separated compartments: Stress granules, which are RNA bodies that form rapidly in the cytoplasm upon cellular stress, and centrosomes, which are sites of microtubule nucleation. We will combine these studies with a quantitative description of the crowded nature of cytoplasm and of its local variations, to provide a direct readout of the impact of excluded volume on molecular assembly in living cells. Taken together, these studies will provide fundamental insights into the structural basis by which cells form biochemical compartments.
Max ERC Funding
1 228 125 €
Duration
Start date: 2018-02-01, End date: 2023-01-31
Project acronym ABRSEIST
Project Antibiotic Resistance: Socio-Economic Determinants and the Role of Information and Salience in Treatment Choice
Researcher (PI) Hannes ULLRICH
Host Institution (HI) DEUTSCHES INSTITUT FUR WIRTSCHAFTSFORSCHUNG DIW (INSTITUT FUR KONJUNKTURFORSCHUNG) EV
Call Details Starting Grant (StG), SH1, ERC-2018-STG
Summary Antibiotics have contributed to a tremendous increase in human well-being, saving many millions of lives. However, antibiotics become obsolete the more they are used as selection pressure promotes the development of resistant bacteria. The World Health Organization has proclaimed antibiotic resistance as a major global threat to public health. Today, 700,000 deaths per year are due to untreatable infections. To win the battle against antibiotic resistance, new policies affecting the supply and demand of existing and new drugs must be designed. I propose new research to identify and evaluate feasible and effective demand-side policy interventions targeting the relevant decision makers: physicians and patients. ABRSEIST will make use of a broad econometric toolset to identify mechanisms linking antibiotic resistance and consumption exploiting a unique combination of physician-patient-level antibiotic resistance, treatment, and socio-economic data. Using machine learning methods adapted for causal inference, theory-driven structural econometric analysis, and randomization in the field it will provide rigorous evidence on effective intervention designs. This research will improve our understanding of how prescribing, resistance, and the effect of antibiotic use on resistance, are distributed in the general population which has important implications for the design of targeted interventions. It will then estimate a structural model of general practitioners’ acquisition and use of information under uncertainty about resistance in prescription choice, allowing counterfactual analysis of information-improving policies such as mandatory diagnostic testing. The large-scale and structural econometric analyses allow flexible identification of physician heterogeneity, which ABRSEIST will exploit to design and evaluate targeted, randomized information nudges in the field. The result will be improved rational use and a toolset applicable in contexts of antibiotic prescribing.
Summary
Antibiotics have contributed to a tremendous increase in human well-being, saving many millions of lives. However, antibiotics become obsolete the more they are used as selection pressure promotes the development of resistant bacteria. The World Health Organization has proclaimed antibiotic resistance as a major global threat to public health. Today, 700,000 deaths per year are due to untreatable infections. To win the battle against antibiotic resistance, new policies affecting the supply and demand of existing and new drugs must be designed. I propose new research to identify and evaluate feasible and effective demand-side policy interventions targeting the relevant decision makers: physicians and patients. ABRSEIST will make use of a broad econometric toolset to identify mechanisms linking antibiotic resistance and consumption exploiting a unique combination of physician-patient-level antibiotic resistance, treatment, and socio-economic data. Using machine learning methods adapted for causal inference, theory-driven structural econometric analysis, and randomization in the field it will provide rigorous evidence on effective intervention designs. This research will improve our understanding of how prescribing, resistance, and the effect of antibiotic use on resistance, are distributed in the general population which has important implications for the design of targeted interventions. It will then estimate a structural model of general practitioners’ acquisition and use of information under uncertainty about resistance in prescription choice, allowing counterfactual analysis of information-improving policies such as mandatory diagnostic testing. The large-scale and structural econometric analyses allow flexible identification of physician heterogeneity, which ABRSEIST will exploit to design and evaluate targeted, randomized information nudges in the field. The result will be improved rational use and a toolset applicable in contexts of antibiotic prescribing.
Max ERC Funding
1 498 920 €
Duration
Start date: 2019-01-01, End date: 2023-12-31
Project acronym ACTMECH
Project Emergent Active Mechanical Behaviour of the Actomyosin Cell Cortex
Researcher (PI) Stephan Wolfgang Grill
Host Institution (HI) TECHNISCHE UNIVERSITAET DRESDEN
Call Details Starting Grant (StG), LS3, ERC-2011-StG_20101109
Summary The cell cortex is a highly dynamic layer of crosslinked actin filaments and myosin molecular motors beneath the cell membrane. It plays a central role in large scale rearrangements that occur inside cells. Many molecular mechanisms contribute to cortex structure and dynamics. However, cell scale physical properties of the cortex are difficult to grasp. This is problematic because for large scale rearrangements inside a cell, such as coherent flow of the cell cortex, it is the cell scale emergent properties that are important for the realization of such events. I will investigate how the actomyosin cytoskeleton behaves at a coarse grained and cellular scale, and will study how this emergent active behaviour is influenced by molecular mechanisms. We will study the cell cortex in the one cell stage C. elegans embryo, which undergoes large scale cortical flow during polarization and cytokinesis. We will combine theory and experiment. We will characterize cortex structure and dynamics with biophysical techniques such as cortical laser ablation and quantitative photobleaching experiments. We will develop and employ novel theoretical approaches to describe the cell scale mechanical behaviour in terms of an active complex fluid. We will utilize genetic approaches to understand how these emergent mechanical properties are influenced by molecular activities. A central goal is to arrive at a coarse grained description of the cortex that can predict future dynamic behaviour from the past structure, which is conceptually similar to how weather forecasting is accomplished. To date, systematic approaches to link molecular scale physical mechanisms to those on cellular scales are missing. This work will open new opportunities for cell biological and cell biophysical research, by providing a methodological approach for bridging scales, for studying emergent and large-scale active mechanical behaviours and linking them to molecular mechanisms.
Summary
The cell cortex is a highly dynamic layer of crosslinked actin filaments and myosin molecular motors beneath the cell membrane. It plays a central role in large scale rearrangements that occur inside cells. Many molecular mechanisms contribute to cortex structure and dynamics. However, cell scale physical properties of the cortex are difficult to grasp. This is problematic because for large scale rearrangements inside a cell, such as coherent flow of the cell cortex, it is the cell scale emergent properties that are important for the realization of such events. I will investigate how the actomyosin cytoskeleton behaves at a coarse grained and cellular scale, and will study how this emergent active behaviour is influenced by molecular mechanisms. We will study the cell cortex in the one cell stage C. elegans embryo, which undergoes large scale cortical flow during polarization and cytokinesis. We will combine theory and experiment. We will characterize cortex structure and dynamics with biophysical techniques such as cortical laser ablation and quantitative photobleaching experiments. We will develop and employ novel theoretical approaches to describe the cell scale mechanical behaviour in terms of an active complex fluid. We will utilize genetic approaches to understand how these emergent mechanical properties are influenced by molecular activities. A central goal is to arrive at a coarse grained description of the cortex that can predict future dynamic behaviour from the past structure, which is conceptually similar to how weather forecasting is accomplished. To date, systematic approaches to link molecular scale physical mechanisms to those on cellular scales are missing. This work will open new opportunities for cell biological and cell biophysical research, by providing a methodological approach for bridging scales, for studying emergent and large-scale active mechanical behaviours and linking them to molecular mechanisms.
Max ERC Funding
1 500 000 €
Duration
Start date: 2011-12-01, End date: 2017-08-31
Project acronym AgeingStemCellFate
Project The Role of Ectopic Adipocyte Progenitors in Age-related Stem Cell Dysfunction, Systemic Inflammation, and Metabolic Disease
Researcher (PI) Tim Julius Schulz
Host Institution (HI) DEUTSCHES INSTITUT FUER ERNAEHRUNGSFORSCHUNG POTSDAM REHBRUECKE
Call Details Starting Grant (StG), LS4, ERC-2012-StG_20111109
Summary Ageing is accompanied by ectopic white adipose tissue depositions in skeletal muscle and other anatomical locations, such as brown adipose tissue and the bone marrow. Ectopic fat accrual contributes to organ dysfunction, systemic insulin resistance, and other perturbations that have been implicated in metabolic diseases.
This research proposal aims to identify the regulatory cues that control the development of ectopic progenitor cells that give rise to this type of fat. It is hypothesized that an age-related dysfunction of the stem cell niche leads to an imbalance between (1) tissue-specific stem cells and (2) fibroblast-like, primarily adipogenic progenitors that reside within many tissues. Novel methodologies that assess stem/progenitor cell characteristics on the single cell level will be combined with animal models of lineage tracing to determine the developmental origin of these adipogenic progenitors and processes that regulate their function.
Notch signalling is a key signalling pathway that relies on direct physical interaction to control stem cell fate. It is proposed that impaired Notch activity contributes to the phenotypical shift of precursor cell distribution in aged tissues.
Lastly, the role of the stem cell niche in ectopic adipocyte progenitor formation will be analyzed. External signals originating from the surrounding niche cells regulate the developmental fate of stem cells. Secreted factors and their role in the formation of ectopic adipocyte precursors during senescence will be identified using a combination of biochemical and systems biology approaches.
Accomplishment of these studies will help to understand the basic processes of stem cell ageing and identify mechanisms of age-related functional decline in tissue regeneration. By targeting the population of tissue-resident adipogenic progenitor cells, therapeutic strategies could be developed to counteract metabolic complications associated with the ageing process.
Summary
Ageing is accompanied by ectopic white adipose tissue depositions in skeletal muscle and other anatomical locations, such as brown adipose tissue and the bone marrow. Ectopic fat accrual contributes to organ dysfunction, systemic insulin resistance, and other perturbations that have been implicated in metabolic diseases.
This research proposal aims to identify the regulatory cues that control the development of ectopic progenitor cells that give rise to this type of fat. It is hypothesized that an age-related dysfunction of the stem cell niche leads to an imbalance between (1) tissue-specific stem cells and (2) fibroblast-like, primarily adipogenic progenitors that reside within many tissues. Novel methodologies that assess stem/progenitor cell characteristics on the single cell level will be combined with animal models of lineage tracing to determine the developmental origin of these adipogenic progenitors and processes that regulate their function.
Notch signalling is a key signalling pathway that relies on direct physical interaction to control stem cell fate. It is proposed that impaired Notch activity contributes to the phenotypical shift of precursor cell distribution in aged tissues.
Lastly, the role of the stem cell niche in ectopic adipocyte progenitor formation will be analyzed. External signals originating from the surrounding niche cells regulate the developmental fate of stem cells. Secreted factors and their role in the formation of ectopic adipocyte precursors during senescence will be identified using a combination of biochemical and systems biology approaches.
Accomplishment of these studies will help to understand the basic processes of stem cell ageing and identify mechanisms of age-related functional decline in tissue regeneration. By targeting the population of tissue-resident adipogenic progenitor cells, therapeutic strategies could be developed to counteract metabolic complications associated with the ageing process.
Max ERC Funding
1 496 444 €
Duration
Start date: 2013-03-01, End date: 2018-02-28
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 ALLELECHOKER
Project DNA binding proteins for treatment of gain of function mutations
Researcher (PI) Enrico Maria Surace
Host Institution (HI) FONDAZIONE TELETHON
Call Details Starting Grant (StG), LS7, ERC-2012-StG_20111109
Summary Zinc finger (ZF) and transcription activator-like effector (TALE) based technologies are been allowing the tailored design of “artificial” DNA-binding proteins targeted to specific and unique DNA genomic sequences. Coupling DNA binding proteins to effectors domains enables the constitution of DNA binding factors for genomic directed transcriptional modulation or targeted genomic editing. We have demonstrated that pairing a ZF DNA binding protein to the transcriptional repressor Kruppel-associated box enables in vivo, the transcriptional repression of one of the most abundantly expressed gene in mammals, the human rhodopsin gene (RHO). We propose to generate RHO DNA binding silencers (“AlleleChoker”), which inactivate RHO either by transcriptional repression or targeted genome modification, irrespectively to wild-type or mutated alleles (mutational-independent approach), and combine RHO endogenous silencing to RHO replacement (silencing-replacement strategy). With this strategy in principle a single bimodal bio-therapeutic will enable the correction of any photoreceptor disease associated with RHO mutation. Adeno-associated viral (AAV) vector-based delivery will be used for photoreceptors gene transfer. Specifically our objectives are: 1) Construction of transcriptional repressors and nucleases for RHO silencing. Characterization and comparison of RHO silencing mediated by transcriptional repressors (ZFR/ TALER) or nucleases (ZFN/ TALEN) to generate genomic directed inactivation by non-homologous end-joining (NHEJ), and refer these results to RNA interference (RNAi) targeted to RHO; 2) RHO silencing in photoreceptors. to determine genome-wide DNA binding specificity of silencers, chromatin modifications and expression profile on human retinal explants; 3) Tuning silencing and replacement. To determine the impact of gene silencing-replacement strategy on disease progression in animal models of autosomal dominant retinitis pigmentosa (adRP) associated to RHO mutations
Summary
Zinc finger (ZF) and transcription activator-like effector (TALE) based technologies are been allowing the tailored design of “artificial” DNA-binding proteins targeted to specific and unique DNA genomic sequences. Coupling DNA binding proteins to effectors domains enables the constitution of DNA binding factors for genomic directed transcriptional modulation or targeted genomic editing. We have demonstrated that pairing a ZF DNA binding protein to the transcriptional repressor Kruppel-associated box enables in vivo, the transcriptional repression of one of the most abundantly expressed gene in mammals, the human rhodopsin gene (RHO). We propose to generate RHO DNA binding silencers (“AlleleChoker”), which inactivate RHO either by transcriptional repression or targeted genome modification, irrespectively to wild-type or mutated alleles (mutational-independent approach), and combine RHO endogenous silencing to RHO replacement (silencing-replacement strategy). With this strategy in principle a single bimodal bio-therapeutic will enable the correction of any photoreceptor disease associated with RHO mutation. Adeno-associated viral (AAV) vector-based delivery will be used for photoreceptors gene transfer. Specifically our objectives are: 1) Construction of transcriptional repressors and nucleases for RHO silencing. Characterization and comparison of RHO silencing mediated by transcriptional repressors (ZFR/ TALER) or nucleases (ZFN/ TALEN) to generate genomic directed inactivation by non-homologous end-joining (NHEJ), and refer these results to RNA interference (RNAi) targeted to RHO; 2) RHO silencing in photoreceptors. to determine genome-wide DNA binding specificity of silencers, chromatin modifications and expression profile on human retinal explants; 3) Tuning silencing and replacement. To determine the impact of gene silencing-replacement strategy on disease progression in animal models of autosomal dominant retinitis pigmentosa (adRP) associated to RHO mutations
Max ERC Funding
1 354 840 €
Duration
Start date: 2013-02-01, End date: 2018-01-31
Project acronym ALLERGUT
Project Mucosal Tolerance and Allergic Predisposition: Does it all start in the gut?
Researcher (PI) Caspar OHNMACHT
Host Institution (HI) HELMHOLTZ ZENTRUM MUENCHEN DEUTSCHES FORSCHUNGSZENTRUM FUER GESUNDHEIT UND UMWELT GMBH
Call Details Starting Grant (StG), LS6, ERC-2016-STG
Summary Currently, more than 30% of all Europeans suffer from one or more allergic disorder but treatment is still mostly symptomatic due to a lack of understanding the underlying causality. Allergies are caused by type 2 immune responses triggered by recognition of harmless antigens. Both genetic and environmental factors have been proposed to favour allergic predisposition and both factors have a huge impact on the symbiotic microbiota and the intestinal immune system. Recently we and others showed that the transcription factor ROR(γt) seems to play a key role in mucosal tolerance in the gut and also regulates intestinal type 2 immune responses.
Based on these results I postulate two major events in the gut for the development of an allergy in the lifetime of an individual: First, a failure to establish mucosal tolerance or anergy constitutes a necessity for the outbreak of allergic symptoms and allergic disease. Second, a certain ‘core’ microbiome or pathway of the intestinal microbiota predispose certain individuals for the later development of allergic disorders. Therefore, I will address the following aims:
1) Influence of ROR(γt) on mucosal tolerance induction and allergic disorders
2) Elucidate the T cell receptor repertoire of intestinal Th2 and ROR(γt)+ Tregs and assess the role of alternative NFκB pathway for induction of mucosal tolerance
3) Identification of ‘core’ microbiome signatures or metabolic pathways that favour allergic predisposition
ALLERGUT will provide ground-breaking knowledge on molecular mechanisms of the failure of mucosal tolerance in the gut and will prove if the resident ROR(γt)+ T(reg) cells can function as a mechanistic starting point for molecular intervention strategies on the background of the hygiene hypothesis. The vision of ALLERGUT is to diagnose mucosal disbalance, prevent and treat allergic disorders even before outbreak and thereby promote Public Health initiative for better living.
Summary
Currently, more than 30% of all Europeans suffer from one or more allergic disorder but treatment is still mostly symptomatic due to a lack of understanding the underlying causality. Allergies are caused by type 2 immune responses triggered by recognition of harmless antigens. Both genetic and environmental factors have been proposed to favour allergic predisposition and both factors have a huge impact on the symbiotic microbiota and the intestinal immune system. Recently we and others showed that the transcription factor ROR(γt) seems to play a key role in mucosal tolerance in the gut and also regulates intestinal type 2 immune responses.
Based on these results I postulate two major events in the gut for the development of an allergy in the lifetime of an individual: First, a failure to establish mucosal tolerance or anergy constitutes a necessity for the outbreak of allergic symptoms and allergic disease. Second, a certain ‘core’ microbiome or pathway of the intestinal microbiota predispose certain individuals for the later development of allergic disorders. Therefore, I will address the following aims:
1) Influence of ROR(γt) on mucosal tolerance induction and allergic disorders
2) Elucidate the T cell receptor repertoire of intestinal Th2 and ROR(γt)+ Tregs and assess the role of alternative NFκB pathway for induction of mucosal tolerance
3) Identification of ‘core’ microbiome signatures or metabolic pathways that favour allergic predisposition
ALLERGUT will provide ground-breaking knowledge on molecular mechanisms of the failure of mucosal tolerance in the gut and will prove if the resident ROR(γt)+ T(reg) cells can function as a mechanistic starting point for molecular intervention strategies on the background of the hygiene hypothesis. The vision of ALLERGUT is to diagnose mucosal disbalance, prevent and treat allergic disorders even before outbreak and thereby promote Public Health initiative for better living.
Max ERC Funding
1 498 175 €
Duration
Start date: 2017-07-01, End date: 2022-06-30
Project acronym ANGIOMET
Project Angiogenesis-metabolism crosstalk in vascular homeostasis and disease
Researcher (PI) Michael Potente
Host Institution (HI) MAX-PLANCK-GESELLSCHAFT ZUR FORDERUNG DER WISSENSCHAFTEN EV
Call Details Starting Grant (StG), LS4, ERC-2012-StG_20111109
Summary "Blood vessels pervade all tissues in the body to supply nutrients and oxygen. Aberrant vessel growth and function are hallmarks of cancer and cardiovascular diseases and they contribute to disease pathogenesis. Antiangiogenic therapeutics have reached the clinic, but limited efficacy and resistance raise unresolved challenges. The current limitations of angiogenic medicine call for a more integrated understanding of the angiogenic process that focuses not only on the instigators of vessel branching but also on mechanisms that sustain vessel growth. Recent insights into fundamental aspects of cell growth move metabolism into spotlight and establish how proliferating cells reprogram their metabolism to provide energy and building blocks for cell replication. During angiogenesis, endothelial cells (ECs) also convert between growth states: although mostly quiescent in adult tissues, ECs divide and migrate rapidly upon angiogenic stimulation. To allow growth of new vessel branches, ECs therefore need to adjust their metabolism to increase energy production and biosynthetic activity. However, the molecular mechanisms that coordinate EC metabolism with angiogenic signalling are not known to date. In this proposal, we put forth the hypothesis that metabolic regulation is a key component of the endothelial angiogenic machinery that is required to sustain vessel growth. Thus, this proposal aims (I) to define transcriptional circuits that link EC growth with metabolism, (II) to explore the regulation of these transcriptional networks by lysine acetylation, a nutrient-regulated protein modification with key functions in metabolism, and (III) to assess the role of sirtuin deacetylases for sensing endothelial energetics during vascular growth. Understanding the principles of angiogenesis-metabolism crosstalk will not only yield novel insights into the basic mechanisms of vessel formation but will also provide unprecedented opportunities for future drug development."
Summary
"Blood vessels pervade all tissues in the body to supply nutrients and oxygen. Aberrant vessel growth and function are hallmarks of cancer and cardiovascular diseases and they contribute to disease pathogenesis. Antiangiogenic therapeutics have reached the clinic, but limited efficacy and resistance raise unresolved challenges. The current limitations of angiogenic medicine call for a more integrated understanding of the angiogenic process that focuses not only on the instigators of vessel branching but also on mechanisms that sustain vessel growth. Recent insights into fundamental aspects of cell growth move metabolism into spotlight and establish how proliferating cells reprogram their metabolism to provide energy and building blocks for cell replication. During angiogenesis, endothelial cells (ECs) also convert between growth states: although mostly quiescent in adult tissues, ECs divide and migrate rapidly upon angiogenic stimulation. To allow growth of new vessel branches, ECs therefore need to adjust their metabolism to increase energy production and biosynthetic activity. However, the molecular mechanisms that coordinate EC metabolism with angiogenic signalling are not known to date. In this proposal, we put forth the hypothesis that metabolic regulation is a key component of the endothelial angiogenic machinery that is required to sustain vessel growth. Thus, this proposal aims (I) to define transcriptional circuits that link EC growth with metabolism, (II) to explore the regulation of these transcriptional networks by lysine acetylation, a nutrient-regulated protein modification with key functions in metabolism, and (III) to assess the role of sirtuin deacetylases for sensing endothelial energetics during vascular growth. Understanding the principles of angiogenesis-metabolism crosstalk will not only yield novel insights into the basic mechanisms of vessel formation but will also provide unprecedented opportunities for future drug development."
Max ERC Funding
1 487 920 €
Duration
Start date: 2012-09-01, End date: 2017-08-31
Project acronym ANGIOPLACE
Project Expression and Methylation Status of Genes Regulating Placental Angiogenesis in Normal, Cloned, IVF and Monoparental Sheep Foetuses
Researcher (PI) Grazyna Ewa Ptak
Host Institution (HI) UNIVERSITA DEGLI STUDI DI TERAMO
Call Details Starting Grant (StG), LS7, ERC-2007-StG
Summary Normal placental angiogenesis is critical for embryonic survival and development. Epigenetic modifications, such as methylation of CpG islands, regulate the expression and imprinting of genes. Epigenetic abnormalities have been observed in embryos from assisted reproductive technologies (ART), which could explain the poor placental vascularisation, embryonic/fetal death, and altered fetal growth in these pregnancies. Both cloned (somatic cell nuclear transfer, or SNCT) and monoparental (parthogenotes, only maternal genes; androgenotes, only paternal genes) embryos provide important models for studying defects in expression and methylation status/imprinting of genes regulating placental function. Our hypothesis is that placental vascular development is compromised during early pregnancy in embryos from ART, in part due to altered expression or imprinting/methylation status of specific genes regulating placental angiogenesis. We will evaluate fetal growth, placental vascular growth, and expression and epigenetic status of genes regulating placental angiogenesis during early pregnancy in 3 Specific Aims: (1) after natural mating; (2) after transfer of biparental embryos from in vitro fertilization, and SCNT; and (3) after transfer of parthenogenetic or androgenetic embryos. These studies will therefore contribute substantially to our understanding of the regulation of placental development and vascularisation during early pregnancy, and could pinpoint the mechanism contributing to embryonic loss and developmental abnormalities in foetuses from ART. Any or all of these observations will contribute to our understanding of and also our ability to successfully employ ART, which are becoming very wide spread and important in human medicine as well as in animal production.
Summary
Normal placental angiogenesis is critical for embryonic survival and development. Epigenetic modifications, such as methylation of CpG islands, regulate the expression and imprinting of genes. Epigenetic abnormalities have been observed in embryos from assisted reproductive technologies (ART), which could explain the poor placental vascularisation, embryonic/fetal death, and altered fetal growth in these pregnancies. Both cloned (somatic cell nuclear transfer, or SNCT) and monoparental (parthogenotes, only maternal genes; androgenotes, only paternal genes) embryos provide important models for studying defects in expression and methylation status/imprinting of genes regulating placental function. Our hypothesis is that placental vascular development is compromised during early pregnancy in embryos from ART, in part due to altered expression or imprinting/methylation status of specific genes regulating placental angiogenesis. We will evaluate fetal growth, placental vascular growth, and expression and epigenetic status of genes regulating placental angiogenesis during early pregnancy in 3 Specific Aims: (1) after natural mating; (2) after transfer of biparental embryos from in vitro fertilization, and SCNT; and (3) after transfer of parthenogenetic or androgenetic embryos. These studies will therefore contribute substantially to our understanding of the regulation of placental development and vascularisation during early pregnancy, and could pinpoint the mechanism contributing to embryonic loss and developmental abnormalities in foetuses from ART. Any or all of these observations will contribute to our understanding of and also our ability to successfully employ ART, which are becoming very wide spread and important in human medicine as well as in animal production.
Max ERC Funding
363 600 €
Duration
Start date: 2008-10-01, End date: 2012-06-30
