Project acronym 1D-Engine
Project 1D-electrons coupled to dissipation: a novel approach for understanding and engineering superconducting materials and devices
Researcher (PI) Adrian KANTIAN
Host Institution (HI) HERIOT-WATT UNIVERSITY
Country United Kingdom
Call Details Starting Grant (StG), PE3, ERC-2017-STG
Summary Correlated electrons are at the forefront of condensed matter theory. Interacting quasi-1D electrons have seen vast progress in analytical and numerical theory, and thus in fundamental understanding and quantitative prediction. Yet, in the 1D limit fluctuations preclude important technological use, particularly of superconductors. In contrast, high-Tc superconductors in 2D/3D are not precluded by fluctuations, but lack a fundamental theory, making prediction and engineering of their properties, a major goal in physics, very difficult. This project aims to combine the advantages of both areas by making major progress in the theory of quasi-1D electrons coupled to an electron bath, in part building on recent breakthroughs (with the PIs extensive involvement) in simulating 1D and 2D electrons with parallelized density matrix renormalization group (pDMRG) numerics. Such theory will fundamentally advance the study of open electron systems, and show how to use 1D materials as elements of new superconducting (SC) devices and materials: 1) It will enable a new state of matter, 1D electrons with true SC order. Fluctuations from the electronic liquid, such as graphene, could also enable nanoscale wires to appear SC at high temperatures. 2) A new approach for the deliberate engineering of a high-Tc superconductor. In 1D, how electrons pair by repulsive interactions is understood and can be predicted. Stabilization by reservoir - formed by a parallel array of many such 1D systems - offers a superconductor for which all factors setting Tc are known and can be optimized. 3) Many existing superconductors with repulsive electron pairing, all presently not understood, can be cast as 1D electrons coupled to a bath. Developing chain-DMFT theory based on pDMRG will allow these materials SC properties to be simulated and understood for the first time. 4) The insights gained will be translated to 2D superconductors to study how they could be enhanced by contact with electronic liquids.
Summary
Correlated electrons are at the forefront of condensed matter theory. Interacting quasi-1D electrons have seen vast progress in analytical and numerical theory, and thus in fundamental understanding and quantitative prediction. Yet, in the 1D limit fluctuations preclude important technological use, particularly of superconductors. In contrast, high-Tc superconductors in 2D/3D are not precluded by fluctuations, but lack a fundamental theory, making prediction and engineering of their properties, a major goal in physics, very difficult. This project aims to combine the advantages of both areas by making major progress in the theory of quasi-1D electrons coupled to an electron bath, in part building on recent breakthroughs (with the PIs extensive involvement) in simulating 1D and 2D electrons with parallelized density matrix renormalization group (pDMRG) numerics. Such theory will fundamentally advance the study of open electron systems, and show how to use 1D materials as elements of new superconducting (SC) devices and materials: 1) It will enable a new state of matter, 1D electrons with true SC order. Fluctuations from the electronic liquid, such as graphene, could also enable nanoscale wires to appear SC at high temperatures. 2) A new approach for the deliberate engineering of a high-Tc superconductor. In 1D, how electrons pair by repulsive interactions is understood and can be predicted. Stabilization by reservoir - formed by a parallel array of many such 1D systems - offers a superconductor for which all factors setting Tc are known and can be optimized. 3) Many existing superconductors with repulsive electron pairing, all presently not understood, can be cast as 1D electrons coupled to a bath. Developing chain-DMFT theory based on pDMRG will allow these materials SC properties to be simulated and understood for the first time. 4) The insights gained will be translated to 2D superconductors to study how they could be enhanced by contact with electronic liquids.
Max ERC Funding
1 491 013 €
Duration
Start date: 2018-10-01, End date: 2024-03-31
Project acronym 2D-PnictoChem
Project Chemistry and Interface Control of Novel 2D-Pnictogen Nanomaterials
Researcher (PI) Gonzalo ABELLAN SAEZ
Host Institution (HI) UNIVERSITAT DE VALENCIA
Country Spain
Call Details Starting Grant (StG), PE5, ERC-2018-STG
Summary 2D-PnictoChem aims at exploring the Chemistry of a novel class of graphene-like 2D layered
elemental materials of group 15, the pnictogens: P, As, Sb, and Bi. In the last few years, these materials
have taken the field of Materials Science by storm since they can outperform and/or complement graphene
properties. Their strongly layer-dependent unique properties range from semiconducting to metallic,
including high carrier mobilities, tunable bandgaps, strong spin-orbit coupling or transparency. However,
the Chemistry of pnictogens is still in its infancy, remaining largely unexplored. This is the niche that
2D-PnictoChem aims to fill. By mastering the interface chemistry, we will develop the assembly of 2Dpnictogens
in complex hybrid heterostructures for the first time. Success will rely on a cross-disciplinary
approach combining both Inorganic- and Organic Chemistry with Solid-state Physics, including: 1)
Synthetizing and exfoliating high quality ultra-thin layer pnictogens, providing reliable access down to
the monolayer limit. 2) Achieving their chemical functionalization via both non-covalent and covalent
approaches in order to tailor at will their properties, decipher reactivity patterns and enable controlled
doping avenues. 3) Developing hybrid architectures through a precise chemical control of the interface,
in order to promote unprecedented access to novel heterostructures. 4) Exploring novel applications
concepts achieving outstanding performances. These are all priorities in the European Union agenda
aimed at securing an affordable, clean energy future by developing more efficient hybrid systems for
batteries, electronic devices or applications in catalysis. The opportunity is unique to reduce Europe’s
dependence on external technology and the PI’s background is ideally suited to tackle these objectives,
counting as well on a multidisciplinary team of international collaborators.
Summary
2D-PnictoChem aims at exploring the Chemistry of a novel class of graphene-like 2D layered
elemental materials of group 15, the pnictogens: P, As, Sb, and Bi. In the last few years, these materials
have taken the field of Materials Science by storm since they can outperform and/or complement graphene
properties. Their strongly layer-dependent unique properties range from semiconducting to metallic,
including high carrier mobilities, tunable bandgaps, strong spin-orbit coupling or transparency. However,
the Chemistry of pnictogens is still in its infancy, remaining largely unexplored. This is the niche that
2D-PnictoChem aims to fill. By mastering the interface chemistry, we will develop the assembly of 2Dpnictogens
in complex hybrid heterostructures for the first time. Success will rely on a cross-disciplinary
approach combining both Inorganic- and Organic Chemistry with Solid-state Physics, including: 1)
Synthetizing and exfoliating high quality ultra-thin layer pnictogens, providing reliable access down to
the monolayer limit. 2) Achieving their chemical functionalization via both non-covalent and covalent
approaches in order to tailor at will their properties, decipher reactivity patterns and enable controlled
doping avenues. 3) Developing hybrid architectures through a precise chemical control of the interface,
in order to promote unprecedented access to novel heterostructures. 4) Exploring novel applications
concepts achieving outstanding performances. These are all priorities in the European Union agenda
aimed at securing an affordable, clean energy future by developing more efficient hybrid systems for
batteries, electronic devices or applications in catalysis. The opportunity is unique to reduce Europe’s
dependence on external technology and the PI’s background is ideally suited to tackle these objectives,
counting as well on a multidisciplinary team of international collaborators.
Max ERC Funding
1 499 419 €
Duration
Start date: 2018-11-01, End date: 2023-10-31
Project acronym 2D4QT
Project 2D Materials for Quantum Technology
Researcher (PI) Christoph STAMPFER
Host Institution (HI) RHEINISCH-WESTFAELISCHE TECHNISCHE HOCHSCHULE AACHEN
Country Germany
Call Details Consolidator Grant (CoG), PE3, ERC-2018-COG
Summary Since its discovery, graphene has been indicated as a promising platform for quantum technologies (QT). The number of theoretical proposal dedicated to this vision has grown steadily, exploring a wide range of directions, ranging from spin and valley qubits, to topologically-protected states. The experimental confirmation of these ideas lagged so far significantly behind, mostly because of material quality problems. The quality of graphene-based devices has however improved dramatically in the past five years, thanks to the advent of the so-called van der Waals (vdW) heteostructures - artificial solids formed by mechanically stacking layers of different two dimensional (2D) materials, such as graphene, hexagonal boron nitride and transition metal dichalcogenides. These new advances open now finally the door to put several of those theoretical proposals to test.
The goal of this project is to assess experimentally the potential of graphene-based heterostructures for QT applications. Specifically, I will push the development of an advanced technological platform for vdW heterostructures, which will allow to give quantitative answers to the following open questions: i) what are the relaxation and coherence times of spin and valley qubits in isotopically purified bilayer graphene (BLG); ii) what is the efficiency of a Cooper-pair splitter based on BLG; and iii) what are the characteristic energy scales of topologically protected quantum states engineered in graphene-based heterostructures.
At the end of this project, I aim at being in the position of saying whether graphene is the horse-worth-betting-on predicted by theory, or whether it still hides surprises in terms of fundamental physics. The technological advancements developed in this project for integrating nanostructured layers into vdW heterostructures will reach even beyond this goal, opening the door to new research directions and possible applications.
Summary
Since its discovery, graphene has been indicated as a promising platform for quantum technologies (QT). The number of theoretical proposal dedicated to this vision has grown steadily, exploring a wide range of directions, ranging from spin and valley qubits, to topologically-protected states. The experimental confirmation of these ideas lagged so far significantly behind, mostly because of material quality problems. The quality of graphene-based devices has however improved dramatically in the past five years, thanks to the advent of the so-called van der Waals (vdW) heteostructures - artificial solids formed by mechanically stacking layers of different two dimensional (2D) materials, such as graphene, hexagonal boron nitride and transition metal dichalcogenides. These new advances open now finally the door to put several of those theoretical proposals to test.
The goal of this project is to assess experimentally the potential of graphene-based heterostructures for QT applications. Specifically, I will push the development of an advanced technological platform for vdW heterostructures, which will allow to give quantitative answers to the following open questions: i) what are the relaxation and coherence times of spin and valley qubits in isotopically purified bilayer graphene (BLG); ii) what is the efficiency of a Cooper-pair splitter based on BLG; and iii) what are the characteristic energy scales of topologically protected quantum states engineered in graphene-based heterostructures.
At the end of this project, I aim at being in the position of saying whether graphene is the horse-worth-betting-on predicted by theory, or whether it still hides surprises in terms of fundamental physics. The technological advancements developed in this project for integrating nanostructured layers into vdW heterostructures will reach even beyond this goal, opening the door to new research directions and possible applications.
Max ERC Funding
1 806 250 €
Duration
Start date: 2019-09-01, End date: 2024-08-31
Project acronym 2DHIBSA
Project Nanoscopic and Hierachical Materials via Living Crystallization-Driven Self-Assembly
Researcher (PI) Ian MANNERS
Host Institution (HI) UNIVERSITY OF BRISTOL
Country United Kingdom
Call Details Advanced Grant (AdG), PE5, ERC-2017-ADG
Summary A key synthetic challenge of widespread interest in chemical science involves the creation of well-defined 2D functional materials that exist on a length-scale of nanometers to microns. In this ambitious 5 year proposal we aim to tackle this issue by exploiting the unique opportunities made possible by recent developments with the living crystallization-driven self-assembly (CDSA) platform. Using this solution processing approach, amphiphilic block copolymers (BCPs) with crystallizable blocks, related amphiphiles, and polymers with charged end groups will be used to predictably construct monodisperse samples of tailored, functional soft matter-based 2D nanostructures with controlled shape, size, and spatially-defined chemistries. Many of the resulting nanostructures will also offer unprecedented opportunities as precursors to materials with hierarchical structures through further solution-based “bottom-up” assembly methods. In addition to fundamental studies, the proposed work also aims to make important impact in the cutting-edge fields of liquid crystals, interface stabilization, catalysis, supramolecular polymers, and hierarchical materials.
Summary
A key synthetic challenge of widespread interest in chemical science involves the creation of well-defined 2D functional materials that exist on a length-scale of nanometers to microns. In this ambitious 5 year proposal we aim to tackle this issue by exploiting the unique opportunities made possible by recent developments with the living crystallization-driven self-assembly (CDSA) platform. Using this solution processing approach, amphiphilic block copolymers (BCPs) with crystallizable blocks, related amphiphiles, and polymers with charged end groups will be used to predictably construct monodisperse samples of tailored, functional soft matter-based 2D nanostructures with controlled shape, size, and spatially-defined chemistries. Many of the resulting nanostructures will also offer unprecedented opportunities as precursors to materials with hierarchical structures through further solution-based “bottom-up” assembly methods. In addition to fundamental studies, the proposed work also aims to make important impact in the cutting-edge fields of liquid crystals, interface stabilization, catalysis, supramolecular polymers, and hierarchical materials.
Max ERC Funding
2 499 597 €
Duration
Start date: 2018-05-01, End date: 2023-04-30
Project acronym 3D-FIREFLUC
Project Taming the particle transport in magnetized plasmas via perturbative fields
Researcher (PI) Eleonora VIEZZER
Host Institution (HI) UNIVERSIDAD DE SEVILLA
Country Spain
Call Details Starting Grant (StG), PE2, ERC-2018-STG
Summary Wave-particle interactions are ubiquitous in nature and play a fundamental role in astrophysical and fusion plasmas. In solar plasmas, magnetohydrodynamic (MHD) fluctuations are thought to be responsible for the heating of the solar corona and the generation of the solar wind. In magnetically confined fusion (MCF) devices, enhanced particle transport induced by MHD fluctuations can deteriorate the plasma confinement, and also endanger the device integrity. MCF devices are an ideal testbed to verify current models and develop mitigation / protection techniques.
The proposed project paves the way for providing active control techniques to tame the MHD induced particle transport in a fusion plasma. A solid understanding of the interaction between energetic particles and MHD instabilities in the presence of electric fields and plasma currents is required to develop such techniques. I will pursue this goal through innovative diagnosis techniques with unprecedented spatio-temporal resolution. Combined with state-of-the-art hybrid MHD codes, a deep insight into the underlying physics mechanism will be gained. The outcome of this research project will have a major impact for next-step MCF devices as I will provide ground-breaking control techniques for mitigating MHD induced particle transport in magnetized plasmas.
The project consists of 3 research lines which follow a bottom-up approach:
(1) Cutting-edge instrumentation, aiming at the new generation of energetic particle and edge current diagnostics.
(2) Unravel the dynamics of energetic particles, electric fields, edge currents and MHD fluctuations.
(3) From lab to space weather: The developed models will revolutionize our understanding of the observed particle acceleration and transport in the solar corona.
Based on this approach, the project represents a gateway between the fusion, astrophysics and space communities opening new avenues for a common basic understanding.
Summary
Wave-particle interactions are ubiquitous in nature and play a fundamental role in astrophysical and fusion plasmas. In solar plasmas, magnetohydrodynamic (MHD) fluctuations are thought to be responsible for the heating of the solar corona and the generation of the solar wind. In magnetically confined fusion (MCF) devices, enhanced particle transport induced by MHD fluctuations can deteriorate the plasma confinement, and also endanger the device integrity. MCF devices are an ideal testbed to verify current models and develop mitigation / protection techniques.
The proposed project paves the way for providing active control techniques to tame the MHD induced particle transport in a fusion plasma. A solid understanding of the interaction between energetic particles and MHD instabilities in the presence of electric fields and plasma currents is required to develop such techniques. I will pursue this goal through innovative diagnosis techniques with unprecedented spatio-temporal resolution. Combined with state-of-the-art hybrid MHD codes, a deep insight into the underlying physics mechanism will be gained. The outcome of this research project will have a major impact for next-step MCF devices as I will provide ground-breaking control techniques for mitigating MHD induced particle transport in magnetized plasmas.
The project consists of 3 research lines which follow a bottom-up approach:
(1) Cutting-edge instrumentation, aiming at the new generation of energetic particle and edge current diagnostics.
(2) Unravel the dynamics of energetic particles, electric fields, edge currents and MHD fluctuations.
(3) From lab to space weather: The developed models will revolutionize our understanding of the observed particle acceleration and transport in the solar corona.
Based on this approach, the project represents a gateway between the fusion, astrophysics and space communities opening new avenues for a common basic understanding.
Max ERC Funding
1 512 250 €
Duration
Start date: 2019-05-01, End date: 2024-04-30
Project acronym 3D-FNPWriting
Project Unprecedented spatial control of porosity and functionality in nanoporous membranes through 3D printing and microscopy for polymer writing
Researcher (PI) Annette ANDRIEU-BRUNSEN
Host Institution (HI) TECHNISCHE UNIVERSITAT DARMSTADT
Country Germany
Call Details Starting Grant (StG), PE5, ERC-2018-STG
Summary Membranes are key materials in our life. Nature offers high performance membranes relying on a parallel local regulation of nanopore structure, functional placement, membrane composition and architecture. Existing technological membranes are key materials in separation, recycling, sensing, energy conversion, being essential components for a sustainable future. But their performance is far away from their natural counterparts. One reason for this performance gap is the lack of 3D nanolocal control in membrane design. This applies to each individual nanopore but as well to the membrane architecture. This proposal aims to implement 3D printing (additive manufacturing, top down) and complex near-field and total internal reflection (TIR) high resolution microscopy induced polymer writing (bottom up) to nanolocally control in hierarchical nanoporous membranes spatially and independent of each other: porosity, pore functionalization, membrane architecture, composition. This disruptive technology platform will make accessible to date unachieved, highly accurate asymmetric nanopores and multifunctional, hierarchical membrane architecture/ composition and thus highly selective, directed, transport with tuneable rates. 3D-FNPWriting will demonstrate this for the increasing class of metal nanoparticle/ salt pollutants aiming for tuneable, selective, directed transport based monitoring and recycling instead of size-based filtration, accumulation into sewerage and distribution into nature. Specifically, the potential of this disruptive technology with respect to transport design will be demonstrated for a) a 3D-printed in-situ functionalized nanoporous fiber architecture and b) a printed, nanolocally near-field and TIR-microscopy polymer functionalized membrane representing a thin separation layer. This will open systematic understanding of nanolocal functional control on transport and new perspectives in water/ energy management for future smart industry/ homes.
Summary
Membranes are key materials in our life. Nature offers high performance membranes relying on a parallel local regulation of nanopore structure, functional placement, membrane composition and architecture. Existing technological membranes are key materials in separation, recycling, sensing, energy conversion, being essential components for a sustainable future. But their performance is far away from their natural counterparts. One reason for this performance gap is the lack of 3D nanolocal control in membrane design. This applies to each individual nanopore but as well to the membrane architecture. This proposal aims to implement 3D printing (additive manufacturing, top down) and complex near-field and total internal reflection (TIR) high resolution microscopy induced polymer writing (bottom up) to nanolocally control in hierarchical nanoporous membranes spatially and independent of each other: porosity, pore functionalization, membrane architecture, composition. This disruptive technology platform will make accessible to date unachieved, highly accurate asymmetric nanopores and multifunctional, hierarchical membrane architecture/ composition and thus highly selective, directed, transport with tuneable rates. 3D-FNPWriting will demonstrate this for the increasing class of metal nanoparticle/ salt pollutants aiming for tuneable, selective, directed transport based monitoring and recycling instead of size-based filtration, accumulation into sewerage and distribution into nature. Specifically, the potential of this disruptive technology with respect to transport design will be demonstrated for a) a 3D-printed in-situ functionalized nanoporous fiber architecture and b) a printed, nanolocally near-field and TIR-microscopy polymer functionalized membrane representing a thin separation layer. This will open systematic understanding of nanolocal functional control on transport and new perspectives in water/ energy management for future smart industry/ homes.
Max ERC Funding
1 499 844 €
Duration
Start date: 2019-04-01, End date: 2024-03-31
Project acronym 3D-PXM
Project 3D Piezoresponse X-ray Microscopy
Researcher (PI) Hugh SIMONS
Host Institution (HI) DANMARKS TEKNISKE UNIVERSITET
Country Denmark
Call Details Starting Grant (StG), PE3, ERC-2018-STG
Summary Polar materials, such as piezoelectrics and ferroelectrics are essential to our modern life, yet they are mostly developed by trial-and-error. Their properties overwhelmingly depend on the defects within them, the majority of which are hidden in the bulk. The road to better materials is via mapping these defects, but our best tool for it – piezoresponse force microscopy (PFM) – is limited to surfaces. 3D-PXM aims to revolutionize our understanding by measuring the local structure-property correlations around individual defects buried deep in the bulk.
This is a completely new kind of microscopy enabling 3D maps of local strain and polarization (i.e. piezoresponse) with 10 nm resolution in mm-sized samples. It is novel, multi-scale and fast enough to capture defect dynamics in real time. Uniquely, it is a full-field method that uses a synthetic-aperture approach to improve both resolution and recover the image phase. This phase is then quantitatively correlated to local polarization and strain via a forward model. 3D-PXM combines advances in X-Ray optics, phase recovery and data analysis to create something transformative. In principle, it can achieve spatial resolution comparable to the best coherent X-Ray microscopy methods while being faster, used on larger samples, and without risk of radiation damage.
For the first time, this opens the door to solving how defects influence bulk properties under real-life conditions. 3D-PXM focuses on three types of defects prevalent in polar materials: grain boundaries, dislocations and polar nanoregions. Individually they address major gaps in the state-of-the-art, while together making great strides towards fully understanding defects. This understanding is expected to inform a new generation of multi-scale models that can account for a material’s full heterogeneity. These models are the first step towards abandoning our tradition of trial-and-error, and with this comes the potential for a new era of polar materials.
Summary
Polar materials, such as piezoelectrics and ferroelectrics are essential to our modern life, yet they are mostly developed by trial-and-error. Their properties overwhelmingly depend on the defects within them, the majority of which are hidden in the bulk. The road to better materials is via mapping these defects, but our best tool for it – piezoresponse force microscopy (PFM) – is limited to surfaces. 3D-PXM aims to revolutionize our understanding by measuring the local structure-property correlations around individual defects buried deep in the bulk.
This is a completely new kind of microscopy enabling 3D maps of local strain and polarization (i.e. piezoresponse) with 10 nm resolution in mm-sized samples. It is novel, multi-scale and fast enough to capture defect dynamics in real time. Uniquely, it is a full-field method that uses a synthetic-aperture approach to improve both resolution and recover the image phase. This phase is then quantitatively correlated to local polarization and strain via a forward model. 3D-PXM combines advances in X-Ray optics, phase recovery and data analysis to create something transformative. In principle, it can achieve spatial resolution comparable to the best coherent X-Ray microscopy methods while being faster, used on larger samples, and without risk of radiation damage.
For the first time, this opens the door to solving how defects influence bulk properties under real-life conditions. 3D-PXM focuses on three types of defects prevalent in polar materials: grain boundaries, dislocations and polar nanoregions. Individually they address major gaps in the state-of-the-art, while together making great strides towards fully understanding defects. This understanding is expected to inform a new generation of multi-scale models that can account for a material’s full heterogeneity. These models are the first step towards abandoning our tradition of trial-and-error, and with this comes the potential for a new era of polar materials.
Max ERC Funding
1 496 941 €
Duration
Start date: 2019-01-01, End date: 2023-12-31
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
Country Germany
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 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
Country France
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 3DMOSHBOND
Project Three-Dimensional Mapping Of a Single Hydrogen Bond
Researcher (PI) Adam Marc SWEETMAN
Host Institution (HI) UNIVERSITY OF LEEDS
Country United Kingdom
Call Details Starting Grant (StG), PE3, ERC-2017-STG
Summary All properties of matter are ultimately governed by the forces between single atoms, but our knowledge of interatomic, and intermolecular, potentials is often derived indirectly.
In 3DMOSHBOND, I outline a program of work designed to create a paradigm shift in the direct measurement of complex interatomic potentials via a fundamental reimagining of how atomic resolution imaging, and force measurement, techniques are applied.
To provide a clear proof of principle demonstration of the power of this concept, I propose to map the strength, shape and extent of single hydrogen bonding (H-bonding) interactions in 3D with sub-Angstrom precision. H-bonding is a key component governing intermolecular interactions, particularly for biologically important molecules. Despite its critical importance, H-bonding is relatively poorly understood, and the IUPAC definition of the H-bond was changed as recently as 2011- highlighting the relevance of a new means to engage with these fundamental interactions.
Hitherto unprecedented resolution and accuracy will be achieved via a creation of a novel layer of vertically oriented H-bonding molecules, functionalisation of the tip of a scanning probe microscope with a single complementary H-bonding molecule, and by complete characterisation of the position of all atoms in the junction. This will place two H-bonding groups “end on” and map the extent, and magnitude, of the H-bond with sub-Angstrom precision for a variety of systems. This investigation of the H-bond will present us with an unparalleled level of information regarding its properties.
Experimental results will be compared with ab initio density functional theory (DFT) simulations, to investigate the extent to which state-of-the-art simulations are able to reproduce the behaviour of the H-bonding interaction. The project will create a new generalised probe for the study of single atomic and molecular interactions.
Summary
All properties of matter are ultimately governed by the forces between single atoms, but our knowledge of interatomic, and intermolecular, potentials is often derived indirectly.
In 3DMOSHBOND, I outline a program of work designed to create a paradigm shift in the direct measurement of complex interatomic potentials via a fundamental reimagining of how atomic resolution imaging, and force measurement, techniques are applied.
To provide a clear proof of principle demonstration of the power of this concept, I propose to map the strength, shape and extent of single hydrogen bonding (H-bonding) interactions in 3D with sub-Angstrom precision. H-bonding is a key component governing intermolecular interactions, particularly for biologically important molecules. Despite its critical importance, H-bonding is relatively poorly understood, and the IUPAC definition of the H-bond was changed as recently as 2011- highlighting the relevance of a new means to engage with these fundamental interactions.
Hitherto unprecedented resolution and accuracy will be achieved via a creation of a novel layer of vertically oriented H-bonding molecules, functionalisation of the tip of a scanning probe microscope with a single complementary H-bonding molecule, and by complete characterisation of the position of all atoms in the junction. This will place two H-bonding groups “end on” and map the extent, and magnitude, of the H-bond with sub-Angstrom precision for a variety of systems. This investigation of the H-bond will present us with an unparalleled level of information regarding its properties.
Experimental results will be compared with ab initio density functional theory (DFT) simulations, to investigate the extent to which state-of-the-art simulations are able to reproduce the behaviour of the H-bonding interaction. The project will create a new generalised probe for the study of single atomic and molecular interactions.
Max ERC Funding
1 971 468 €
Duration
Start date: 2018-01-01, End date: 2023-12-31