Project acronym ACOPS
Project Advanced Coherent Ultrafast Laser Pulse Stacking
Researcher (PI) Jens Limpert
Host Institution (HI) FRIEDRICH-SCHILLER-UNIVERSITAT JENA
Country Germany
Call Details Consolidator Grant (CoG), PE2, ERC-2013-CoG
Summary "An important driver of scientific progress has always been the envisioning of applications far beyond existing technological capabilities. Such thinking creates new challenges for physicists, driven by the groundbreaking nature of the anticipated application. In the case of laser physics, one of these applications is laser wake-field particle acceleration and possible future uses thereof, such as in collider experiments, or for medical applications such as cancer treatment. To accelerate electrons and positrons to TeV-energies, a laser architecture is required that allows for the combination of high efficiency, Petawatt peak powers, and Megawatt average powers. Developing such a laser system would be a challenging task that might take decades of aggressive research, development, and, most important, revolutionary approaches and innovative ideas.
The goal of the ACOPS project is to develop a compact, efficient, scalable, and cost-effective high-average and high-peak power ultra-short pulse laser concept.
The proposed approach to this goal relies on the spatially and temporally separated amplification of ultrashort laser pulses in waveguide structures, followed by coherent combination into a single train of pulses with increased average power and pulse energy. This combination can be realized through the coherent addition of the output beams of spatially separated amplifiers, combined with the pulse stacking of temporally separated pulses in passive enhancement cavities, employing a fast-switching element as cavity dumper.
Therefore, the three main tasks are the development of kW-class high-repetition-rate driving lasers, the investigation of non-steady state pulse enhancement in passive cavities, and the development of a suitable dumping element.
If successful, the proposed concept would undoubtedly provide a tool that would allow researchers to surpass the current limits in high-field physics and accelerator science."
Summary
"An important driver of scientific progress has always been the envisioning of applications far beyond existing technological capabilities. Such thinking creates new challenges for physicists, driven by the groundbreaking nature of the anticipated application. In the case of laser physics, one of these applications is laser wake-field particle acceleration and possible future uses thereof, such as in collider experiments, or for medical applications such as cancer treatment. To accelerate electrons and positrons to TeV-energies, a laser architecture is required that allows for the combination of high efficiency, Petawatt peak powers, and Megawatt average powers. Developing such a laser system would be a challenging task that might take decades of aggressive research, development, and, most important, revolutionary approaches and innovative ideas.
The goal of the ACOPS project is to develop a compact, efficient, scalable, and cost-effective high-average and high-peak power ultra-short pulse laser concept.
The proposed approach to this goal relies on the spatially and temporally separated amplification of ultrashort laser pulses in waveguide structures, followed by coherent combination into a single train of pulses with increased average power and pulse energy. This combination can be realized through the coherent addition of the output beams of spatially separated amplifiers, combined with the pulse stacking of temporally separated pulses in passive enhancement cavities, employing a fast-switching element as cavity dumper.
Therefore, the three main tasks are the development of kW-class high-repetition-rate driving lasers, the investigation of non-steady state pulse enhancement in passive cavities, and the development of a suitable dumping element.
If successful, the proposed concept would undoubtedly provide a tool that would allow researchers to surpass the current limits in high-field physics and accelerator science."
Max ERC Funding
1 881 040 €
Duration
Start date: 2014-02-01, End date: 2019-01-31
Project acronym ANYON
Project Engineering and exploring anyonic quantum gases
Researcher (PI) Christof WEITENBERG
Host Institution (HI) UNIVERSITAET HAMBURG
Country Germany
Call Details Starting Grant (StG), PE2, ERC-2018-STG
Summary This project enters the experimental investigation of anyonic quantum gases. We will study anyons – conjectured particles with a statistical exchange phase anywhere between 0 and π – in different many-body systems. This progress will be enabled by a unique approach of bringing together artificial gauge fields and quantum gas microscopes for ultracold atoms.
Specifically, we will implement the 1D anyon Hubbard model via a lattice shaking protocol that imprints density-dependent Peierls phases. By engineering the statistical exchange phase, we can continuously tune between bosons and fermions and explore a statistically-induced quantum phase transition. We will monitor the continuous fermionization via the build-up of Friedel oscillations. Using state-of-the-art cold atom technology, we will thus open the physics of anyons to experimental research and address open questions related to their fractional exclusion statistics.
Secondly, we will create fractional quantum Hall systems in rapidly rotating microtraps. Using the quantum gas microscope, we will i) control the optical potentials at a level which allows approaching the centrifugal limit and ii) use small atom numbers equal to the inserted angular momentum quantum number. The strongly-correlated ground states such as the Laughlin state can be identified via their characteristic density correlations. Of particular interest are the quasihole excitations, whose predicted anyonic exchange statistics have not been directly observed to date. We will probe and test their statistics via the characteristic counting sequence in the excitation spectrum. Furthermore, we will test ideas to transfer anyonic properties of the excitations to a second tracer species. This approach will enable us to both probe the fractional exclusion statistics of the excitations and to create a 2D anyonic quantum gas.
In the long run, these techniques open a path to also study non-Abelian anyons with ultracold atoms.
Summary
This project enters the experimental investigation of anyonic quantum gases. We will study anyons – conjectured particles with a statistical exchange phase anywhere between 0 and π – in different many-body systems. This progress will be enabled by a unique approach of bringing together artificial gauge fields and quantum gas microscopes for ultracold atoms.
Specifically, we will implement the 1D anyon Hubbard model via a lattice shaking protocol that imprints density-dependent Peierls phases. By engineering the statistical exchange phase, we can continuously tune between bosons and fermions and explore a statistically-induced quantum phase transition. We will monitor the continuous fermionization via the build-up of Friedel oscillations. Using state-of-the-art cold atom technology, we will thus open the physics of anyons to experimental research and address open questions related to their fractional exclusion statistics.
Secondly, we will create fractional quantum Hall systems in rapidly rotating microtraps. Using the quantum gas microscope, we will i) control the optical potentials at a level which allows approaching the centrifugal limit and ii) use small atom numbers equal to the inserted angular momentum quantum number. The strongly-correlated ground states such as the Laughlin state can be identified via their characteristic density correlations. Of particular interest are the quasihole excitations, whose predicted anyonic exchange statistics have not been directly observed to date. We will probe and test their statistics via the characteristic counting sequence in the excitation spectrum. Furthermore, we will test ideas to transfer anyonic properties of the excitations to a second tracer species. This approach will enable us to both probe the fractional exclusion statistics of the excitations and to create a 2D anyonic quantum gas.
In the long run, these techniques open a path to also study non-Abelian anyons with ultracold atoms.
Max ERC Funding
1 497 500 €
Duration
Start date: 2019-01-01, End date: 2023-12-31
Project acronym BathyBiome
Project The Symbiome of Bathymodiolus Mussels from Hydrothermal Vents: From the Genome
to the Environment
Researcher (PI) Nicole Dubilier
Host Institution (HI) Klinik Max Planck Institut für Psychiatrie
Country Germany
Call Details Advanced Grant (AdG), LS8, ERC-2013-ADG
Summary The discovery of deep-sea hydrothermal vents in 1977 was one of the most profound findings of the 20th century, revolutionizing our perception of energy sources fueling primary productivity on Earth. These ecosystems are based on chemosynthesis, that is the fixation of carbon dioxide into organic compounds as in photosynthesis, but using inorganic compounds such as sulfide, methane or hydrogen, as energy sources instead of sunlight. Hydrothermal vents support tremendous biomass and productivity of which the majority is generated through symbiotic microbe-animal associations. Bathymodiolus mussels are able to build extraordinarily large and productive communities at hydrothermal vents because they harbor symbiotic bacteria that use inorganic energy sources from the vent fluids to feed their hosts via carbon fixation. In addition to their beneficial symbionts, the mussels are infected by a novel bacterial parasite that exclusively invades and multiplies in their nuclei. In the work proposed here, I will use a wide array of tools that range from deep-sea in situ instruments to sophisticated molecular, 'omic' and imaging analyses to study the microbiome associated with Bathymodiolus mussels. The proposed
research bridges biogeochemistry, ecological and evolutionary biology, and molecular microbiology to develop a systematic understanding of the symbiotic interactions between microbes, their hosts, and their environment in one of the most extreme and fascinating habitats on Earth, hydrothermal vents.
Summary
The discovery of deep-sea hydrothermal vents in 1977 was one of the most profound findings of the 20th century, revolutionizing our perception of energy sources fueling primary productivity on Earth. These ecosystems are based on chemosynthesis, that is the fixation of carbon dioxide into organic compounds as in photosynthesis, but using inorganic compounds such as sulfide, methane or hydrogen, as energy sources instead of sunlight. Hydrothermal vents support tremendous biomass and productivity of which the majority is generated through symbiotic microbe-animal associations. Bathymodiolus mussels are able to build extraordinarily large and productive communities at hydrothermal vents because they harbor symbiotic bacteria that use inorganic energy sources from the vent fluids to feed their hosts via carbon fixation. In addition to their beneficial symbionts, the mussels are infected by a novel bacterial parasite that exclusively invades and multiplies in their nuclei. In the work proposed here, I will use a wide array of tools that range from deep-sea in situ instruments to sophisticated molecular, 'omic' and imaging analyses to study the microbiome associated with Bathymodiolus mussels. The proposed
research bridges biogeochemistry, ecological and evolutionary biology, and molecular microbiology to develop a systematic understanding of the symbiotic interactions between microbes, their hosts, and their environment in one of the most extreme and fascinating habitats on Earth, hydrothermal vents.
Max ERC Funding
2 499 122 €
Duration
Start date: 2014-02-01, End date: 2019-01-31
Project acronym BRAIN-MATCH
Project Matching CNS Lineage Maps with Molecular Brain Tumor Portraits for Translational Exploitation
Researcher (PI) Stefan PFISTER
Host Institution (HI) DEUTSCHES KREBSFORSCHUNGSZENTRUM HEIDELBERG
Country Germany
Call Details Consolidator Grant (CoG), LS2, ERC-2018-COG
Summary Brain tumors represent an extremely heterogeneous group of more than 100 different molecularly distinct diseases, many of which are still almost uniformly lethal despite five decades of clinical trials. In contrast to hematologic malignancies and carcinomas, the cell-of-origin for the vast majority of these entities is unknown. This knowledge gap currently precludes a comprehensive understanding of tumor biology and also limits translational exploitation (e.g., utilizing lineage targets for novel therapies and circulating brain tumor cells for liquid biopsies).
The BRAIN-MATCH project represents an ambitious program to address this challenge and unmet medical need by taking an approach that (i) extensively utilizes existing molecular profiles of more than 30,000 brain tumor samples covering more than 100 different entities, publicly available single-cell sequencing data of normal brain regions, and bulk normal tissue data at different times of development across different species; (ii) generates unprecedented maps of normal human CNS development by using state-of-the art novel technologies; (iii) matches these molecular portraits of normal cell types with tumor datasets in order to identify specific cell-of-origin populations for individual tumor entities; and (iv) validates the most promising cell-of-origin populations and tumor-specific lineage and/or surface markers in vivo.
The expected outputs of BRAIN-MATCH are four-fold: (i) delivery of an unprecedented atlas of human normal CNS development, which will also be of great relevance for diverse fields other than cancer; (ii) functional validation of at least three lineage targets; (iii) isolation and molecular characterization of circulating brain tumor cells from patients´ blood for at least five tumor entities; and (iv) generation of at least three novel mouse models of brain tumor entities for which currently no faithful models exist.
Summary
Brain tumors represent an extremely heterogeneous group of more than 100 different molecularly distinct diseases, many of which are still almost uniformly lethal despite five decades of clinical trials. In contrast to hematologic malignancies and carcinomas, the cell-of-origin for the vast majority of these entities is unknown. This knowledge gap currently precludes a comprehensive understanding of tumor biology and also limits translational exploitation (e.g., utilizing lineage targets for novel therapies and circulating brain tumor cells for liquid biopsies).
The BRAIN-MATCH project represents an ambitious program to address this challenge and unmet medical need by taking an approach that (i) extensively utilizes existing molecular profiles of more than 30,000 brain tumor samples covering more than 100 different entities, publicly available single-cell sequencing data of normal brain regions, and bulk normal tissue data at different times of development across different species; (ii) generates unprecedented maps of normal human CNS development by using state-of-the art novel technologies; (iii) matches these molecular portraits of normal cell types with tumor datasets in order to identify specific cell-of-origin populations for individual tumor entities; and (iv) validates the most promising cell-of-origin populations and tumor-specific lineage and/or surface markers in vivo.
The expected outputs of BRAIN-MATCH are four-fold: (i) delivery of an unprecedented atlas of human normal CNS development, which will also be of great relevance for diverse fields other than cancer; (ii) functional validation of at least three lineage targets; (iii) isolation and molecular characterization of circulating brain tumor cells from patients´ blood for at least five tumor entities; and (iv) generation of at least three novel mouse models of brain tumor entities for which currently no faithful models exist.
Max ERC Funding
1 999 875 €
Duration
Start date: 2019-05-01, End date: 2024-04-30
Project acronym CHROMOTHRIPSIS
Project Dissecting the Molecular Mechanism of Catastrophic DNA Rearrangement in Cancer
Researcher (PI) Jan Oliver Korbel
Host Institution (HI) EUROPEAN MOLECULAR BIOLOGY LABORATORY
Country Germany
Call Details Starting Grant (StG), LS2, ERC-2013-StG
Summary Recent cancer genome analyses have led to the discovery of a process involving massive genome structural rearrangement (SR) formation in a one-step, cataclysmic event, coined chromothripsis. The term chromothripsis (chromo from chromosome; thripsis for shattering into pieces) stands for a hypothetical process in which individual chromosomes are pulverised, resulting in a multitude of fragments, some of which are lost to the cell whereas others are erroneously rejoined. Compelling evidence was presented that chromothripsis plays a crucial role in the development, or progression of a notable subset of human cancers – thus, tumorigensis models involving gradual acquisitions of alterations may need to be revised in these cancers.
Presently, chromothripsis lacks a mechanistic basis. We recently showed that in childhood medulloblastoma brain tumours driven by Sonic Hedgehog (Shh) signalling, chromothripsis is linked with predisposing TP53 mutations. Thus, rather than occurring in isolation, chromothripsis appears to be prone to happen in conjunction with (or instigated by) gradually acquired alterations, or in the context of active signalling pathways, the inference of which may lead to further mechanistic insights. Using such rationale, I propose to dissect the mechanism behind chromothripsis using interdisciplinary approaches. First, we will develop a computational approach to accurately detect chromothripsis. Second, we will use this approach to link chromothripsis with novel factors and contexts. Third, we will develop highly controllable cell line-based systems to test concrete mechanistic hypotheses, thereby taking into account our data on linked factors and contexts. Fourth, we will generate transcriptome data to monitor pathways involved in inducing chromothripsis, and such involved in coping with the massive SRs occurring. We will also combine findings from all these approaches to build a comprehensive model of chromothripsis and its associated pathways.
Summary
Recent cancer genome analyses have led to the discovery of a process involving massive genome structural rearrangement (SR) formation in a one-step, cataclysmic event, coined chromothripsis. The term chromothripsis (chromo from chromosome; thripsis for shattering into pieces) stands for a hypothetical process in which individual chromosomes are pulverised, resulting in a multitude of fragments, some of which are lost to the cell whereas others are erroneously rejoined. Compelling evidence was presented that chromothripsis plays a crucial role in the development, or progression of a notable subset of human cancers – thus, tumorigensis models involving gradual acquisitions of alterations may need to be revised in these cancers.
Presently, chromothripsis lacks a mechanistic basis. We recently showed that in childhood medulloblastoma brain tumours driven by Sonic Hedgehog (Shh) signalling, chromothripsis is linked with predisposing TP53 mutations. Thus, rather than occurring in isolation, chromothripsis appears to be prone to happen in conjunction with (or instigated by) gradually acquired alterations, or in the context of active signalling pathways, the inference of which may lead to further mechanistic insights. Using such rationale, I propose to dissect the mechanism behind chromothripsis using interdisciplinary approaches. First, we will develop a computational approach to accurately detect chromothripsis. Second, we will use this approach to link chromothripsis with novel factors and contexts. Third, we will develop highly controllable cell line-based systems to test concrete mechanistic hypotheses, thereby taking into account our data on linked factors and contexts. Fourth, we will generate transcriptome data to monitor pathways involved in inducing chromothripsis, and such involved in coping with the massive SRs occurring. We will also combine findings from all these approaches to build a comprehensive model of chromothripsis and its associated pathways.
Max ERC Funding
1 471 964 €
Duration
Start date: 2014-04-01, End date: 2019-01-31
Project acronym CULTSONG
Project Culture as an evolutionary force: Does song learning accelerate speciation in a bat ring species?
Researcher (PI) Mirjam KNoeRNSCHILD
Host Institution (HI) MUSEUM FUR NATURKUNDE - LEIBNIZ-INSTITUT FUR EVOLUTIONS- UND BIODIVERSITATSFORSCHUNG AN DER HUMBOLDT-UNIVERSITAT ZU BERLIN
Country Germany
Call Details Starting Grant (StG), LS8, ERC-2018-STG
Summary Culture is highly relevant for human evolution but whether animal culture can be an evolutionary force that promotes speciation is an open and highly contested issue. While culturally induced song divergence can be correlated with increased speciation rates in songbirds, it is hard to resolve whether cultural differences are promoting speciation or vice versa. Studying ring species is a perfect solution for this problem since they illustrate divergence in space instead of time, thus allowing us to determine whether cultural differences are causes or consequences of speciation. A ring species originates from a population that expands around an uninhabitable barrier and gradually diverges until the terminal forms are reproductively isolated upon secondary contact. We will study whether culturally induced song divergence accelerates speciation in the bat Saccopteryx bilineata, the first known mammalian ring species. Cultural differences between S. bilineata populations are manifested in distinct and temporally stable song dialects which juvenile males learn from adults. First, we will study song divergence around the ring and the relative contribution of song dialects to reproductive isolation of the co-occurring terminal forms of the ring. Second, we will study potential genetic predispositions for learning specific song dialects and investigate neurogenetic mechanisms involved in mammalian song learning. Third, we will reconstruct the history, evolutionary patterns and processes of speciation in a ring using a genomic approach in S. bilineata and its sympatric sister species. This comparative approach will allow us to unravel factors involved in the rapid divergence of S. bilineata on a small spatial scale. In synthesis, we will be able to determine whether sexually selected, culturally transmitted traits can accelerate speciation and elucidate the role of culture as an evolutionary force.
Summary
Culture is highly relevant for human evolution but whether animal culture can be an evolutionary force that promotes speciation is an open and highly contested issue. While culturally induced song divergence can be correlated with increased speciation rates in songbirds, it is hard to resolve whether cultural differences are promoting speciation or vice versa. Studying ring species is a perfect solution for this problem since they illustrate divergence in space instead of time, thus allowing us to determine whether cultural differences are causes or consequences of speciation. A ring species originates from a population that expands around an uninhabitable barrier and gradually diverges until the terminal forms are reproductively isolated upon secondary contact. We will study whether culturally induced song divergence accelerates speciation in the bat Saccopteryx bilineata, the first known mammalian ring species. Cultural differences between S. bilineata populations are manifested in distinct and temporally stable song dialects which juvenile males learn from adults. First, we will study song divergence around the ring and the relative contribution of song dialects to reproductive isolation of the co-occurring terminal forms of the ring. Second, we will study potential genetic predispositions for learning specific song dialects and investigate neurogenetic mechanisms involved in mammalian song learning. Third, we will reconstruct the history, evolutionary patterns and processes of speciation in a ring using a genomic approach in S. bilineata and its sympatric sister species. This comparative approach will allow us to unravel factors involved in the rapid divergence of S. bilineata on a small spatial scale. In synthesis, we will be able to determine whether sexually selected, culturally transmitted traits can accelerate speciation and elucidate the role of culture as an evolutionary force.
Max ERC Funding
1 492 911 €
Duration
Start date: 2019-05-01, End date: 2024-04-30
Project acronym EntangleUltraCold
Project Entanglement in Strongly Correlated Quantum Many-Body Systems with Ultracold Atoms
Researcher (PI) Daniel Guenther GREIF
Host Institution (HI) RUPRECHT-KARLS-UNIVERSITAET HEIDELBERG
Country Germany
Call Details Starting Grant (StG), PE2, ERC-2018-STG
Summary Entanglement plays a central role for strongly correlated quantum many-body systems and is considered to be the root for a number of surprising emergent phenomena in solids such as high-temperature superconductivity or fractional Quantum Hall states. Entanglement detection in these systems is an important target of current research, but has so far remained elusive owing to the fine control required and high demands on statistical sampling.
The goal of this project is to realize strongly correlated quantum systems close to the ground state using quantum annealing of ultracold fermionic atoms, and to study the character, strength and role of entanglement. We will construct a novel type of cold atom experiment, which makes use of optical tweezers and Raman sideband cooling. This will allow a 100-fold improvement in the experimental repetition rate compared to conventional experiments and allow reaching the ground state in systems of up to 7x7 sites. The flexibility of the moving optical tweezers will facilitate implementing entanglement measures, including concurrence, quantum-state tomography and entanglement entropy. Our primary research objective is studying entanglement in the doped Hubbard model, where a variety of strongly correlated systems are expected, as well as the role of entanglement in thermalizing out-of-equilibrium samples. In a later stage we will focus on frustrated systems in triangular lattices and honeycomb geometries, and also interacting topological states.
Our experiments will have a far-reaching impact on condensed matter research, as it will be the first platform for experimental exploration of the role of entanglement in strongly correlated fermionic many-body systems. Our insights will be beyond the capabilities of numerical simulations and we envision that the project will lead to a better understanding of complex quantum phenomena, and may ultimately drive the discovery of novel quantum materials.
Summary
Entanglement plays a central role for strongly correlated quantum many-body systems and is considered to be the root for a number of surprising emergent phenomena in solids such as high-temperature superconductivity or fractional Quantum Hall states. Entanglement detection in these systems is an important target of current research, but has so far remained elusive owing to the fine control required and high demands on statistical sampling.
The goal of this project is to realize strongly correlated quantum systems close to the ground state using quantum annealing of ultracold fermionic atoms, and to study the character, strength and role of entanglement. We will construct a novel type of cold atom experiment, which makes use of optical tweezers and Raman sideband cooling. This will allow a 100-fold improvement in the experimental repetition rate compared to conventional experiments and allow reaching the ground state in systems of up to 7x7 sites. The flexibility of the moving optical tweezers will facilitate implementing entanglement measures, including concurrence, quantum-state tomography and entanglement entropy. Our primary research objective is studying entanglement in the doped Hubbard model, where a variety of strongly correlated systems are expected, as well as the role of entanglement in thermalizing out-of-equilibrium samples. In a later stage we will focus on frustrated systems in triangular lattices and honeycomb geometries, and also interacting topological states.
Our experiments will have a far-reaching impact on condensed matter research, as it will be the first platform for experimental exploration of the role of entanglement in strongly correlated fermionic many-body systems. Our insights will be beyond the capabilities of numerical simulations and we envision that the project will lead to a better understanding of complex quantum phenomena, and may ultimately drive the discovery of novel quantum materials.
Max ERC Funding
1 787 564 €
Duration
Start date: 2019-08-01, End date: 2024-07-31
Project acronym EpiRIME
Project Epigenetic Reprogramming, Inheritance and Memory: Dissect epigenetic transitions at fertilisation and early embryogenesis
Researcher (PI) Nicola Iovino
Host Institution (HI) MAX-PLANCK-GESELLSCHAFT ZUR FORDERUNG DER WISSENSCHAFTEN EV
Country Germany
Call Details Consolidator Grant (CoG), LS2, ERC-2018-COG
Summary During gametogenesis, germ cells undergo profound chromatin reorganisation, condensation and transcriptional shutdown. Upon fertilization, gamete chromatin is epigenetically reprogrammed, generating a totipotent zygote that can give rise to all cell types of the adult organism. The maternal factors that reprogram gametes to totipotency are unknown. The current dogma suggests that the parental epigenetic information must be erased in order to establish totipotency.
In contrast, we have recently discovered that maternal gametes transmit the epigenetic H3K27me3 histone modification to the next generation (Zenk et al., Science, 2017) adding to increasing evidence suggesting that gametes convey more than just DNA to the offspring. Nevertheless, the underlying mechanisms and the impact of epigenetic inheritance through the gametes are not yet fully resolved. Critically, the mechanisms and impact of (i) paternal gamete reprogramming, (ii) paternal epigenetic inheritance and (iii) de novo establishment of the zygotic epigenome remain essentially unknown.
The objective of this proposal is to unravel the fundamental principles underlying these three major epigenetic transitions in vivo in Drosophila.
We will achieve our objective via three aims: (i) We will investigate the mechanisms underlying the reprogramming of sperm chromatin at fertilization. Specifically, we will determine the nature and extent of the contributions of two proteins essential for sperm chromatin reprogramming (ii) We will examine the mechanism of histone H3K27me3 inheritance through the paternal germline (iii) We will genetically dissect the de novo establishment of constitutive heterochromatin in the newly formed zygote.
Our investigations of these epigenetic transitions are expected to reveal novel insights into the first steps in the formation of life, and to ultimately advance reproductive and regenerative medicine.
Summary
During gametogenesis, germ cells undergo profound chromatin reorganisation, condensation and transcriptional shutdown. Upon fertilization, gamete chromatin is epigenetically reprogrammed, generating a totipotent zygote that can give rise to all cell types of the adult organism. The maternal factors that reprogram gametes to totipotency are unknown. The current dogma suggests that the parental epigenetic information must be erased in order to establish totipotency.
In contrast, we have recently discovered that maternal gametes transmit the epigenetic H3K27me3 histone modification to the next generation (Zenk et al., Science, 2017) adding to increasing evidence suggesting that gametes convey more than just DNA to the offspring. Nevertheless, the underlying mechanisms and the impact of epigenetic inheritance through the gametes are not yet fully resolved. Critically, the mechanisms and impact of (i) paternal gamete reprogramming, (ii) paternal epigenetic inheritance and (iii) de novo establishment of the zygotic epigenome remain essentially unknown.
The objective of this proposal is to unravel the fundamental principles underlying these three major epigenetic transitions in vivo in Drosophila.
We will achieve our objective via three aims: (i) We will investigate the mechanisms underlying the reprogramming of sperm chromatin at fertilization. Specifically, we will determine the nature and extent of the contributions of two proteins essential for sperm chromatin reprogramming (ii) We will examine the mechanism of histone H3K27me3 inheritance through the paternal germline (iii) We will genetically dissect the de novo establishment of constitutive heterochromatin in the newly formed zygote.
Our investigations of these epigenetic transitions are expected to reveal novel insights into the first steps in the formation of life, and to ultimately advance reproductive and regenerative medicine.
Max ERC Funding
1 997 500 €
Duration
Start date: 2019-07-01, End date: 2024-06-30
Project acronym EVOCLOCK
Project From Evolution to Clockworks:Unravelling the molecular basis of circalunar clocks
Researcher (PI) Tobias KAISER
Host Institution (HI) MAX-PLANCK-GESELLSCHAFT ZUR FORDERUNG DER WISSENSCHAFTEN EV
Country Germany
Call Details Starting Grant (StG), LS8, ERC-2018-STG
Summary Circalunar clocks are endogenous biological clocks, which allow organisms to time development and reproduction to lunar phase. They are common in marine organisms, but their molecular basis is still entirely unknown. Candidate gene approaches have failed so far. In the marine midge Clunio marinus (Diptera: Chironomidae), I can elegantly overcome this problem by exploiting an array of local genetic adaptations in circalunar timing. Through evolutionary analysis, QTL mapping and genome screens my group currently produces evidence-based circalunar candidate genes without any need for prior knowledge or assumptions.
In this ERC proposal, I aim to take this work to the next level and identify the molecular and cellular basis of circalunar clocks. I will establish molecular tools for Clunio and use them to confirm and characterize circalunar clock candidate genes. Specifically, I aim to: (WP1) Establish genome editing and confirm candidate genes via knockout and allelic replacement. (WP2) Study gene expression modules across the lunar cycle and identify the transcriptional regulators that exert circalunar control on development and maturation. (WP3) Describe Clunio’s larval nervous system and trace circalunar clock sensory input pathways to their convergence point. This will identify the cellular substrate of the circalunar clock. (WP4) Settle the on-going debate on the role of circadian clocks in circalunar timing. I will particularly study the role of the famous period gene.
In the future, this molecular endeavour will also boost evolutionary work: Clunio will provide insights into fundamental questions, such as the role of genome architecture in local adaptation. But immediately, unravelling the molecular basis of circalunar clocks will be a breakthrough in chronobiology. It will inspire new ideas and experiments. Comparing circalunar to circadian clocks, we will for the first time be able to see basic principles in the molecular design of biological clocks.
Summary
Circalunar clocks are endogenous biological clocks, which allow organisms to time development and reproduction to lunar phase. They are common in marine organisms, but their molecular basis is still entirely unknown. Candidate gene approaches have failed so far. In the marine midge Clunio marinus (Diptera: Chironomidae), I can elegantly overcome this problem by exploiting an array of local genetic adaptations in circalunar timing. Through evolutionary analysis, QTL mapping and genome screens my group currently produces evidence-based circalunar candidate genes without any need for prior knowledge or assumptions.
In this ERC proposal, I aim to take this work to the next level and identify the molecular and cellular basis of circalunar clocks. I will establish molecular tools for Clunio and use them to confirm and characterize circalunar clock candidate genes. Specifically, I aim to: (WP1) Establish genome editing and confirm candidate genes via knockout and allelic replacement. (WP2) Study gene expression modules across the lunar cycle and identify the transcriptional regulators that exert circalunar control on development and maturation. (WP3) Describe Clunio’s larval nervous system and trace circalunar clock sensory input pathways to their convergence point. This will identify the cellular substrate of the circalunar clock. (WP4) Settle the on-going debate on the role of circadian clocks in circalunar timing. I will particularly study the role of the famous period gene.
In the future, this molecular endeavour will also boost evolutionary work: Clunio will provide insights into fundamental questions, such as the role of genome architecture in local adaptation. But immediately, unravelling the molecular basis of circalunar clocks will be a breakthrough in chronobiology. It will inspire new ideas and experiments. Comparing circalunar to circadian clocks, we will for the first time be able to see basic principles in the molecular design of biological clocks.
Max ERC Funding
1 499 728 €
Duration
Start date: 2019-01-01, End date: 2023-12-31
Project acronym EVOLMAPPING
Project An integrated assessment of recent evolutionary change
through genome wide mapping of regulatory changes and signatures of selection in natural sculpin (Cottus) hybrids
Researcher (PI) Arne W. Nolte
Host Institution (HI) CARL VON OSSIETZKY UNIVERSITAET OLDENBURG
Country Germany
Call Details Starting Grant (StG), LS8, ERC-2013-StG
Summary It is the unprecedented access to genome wide data that highlights the potential of current evolutionary studies and this proposal aims at exploiting this progress to analyze evolutionary processes in a well-established fish system of hybrid speciation. We study natural populations of freshwater fish referred to as sculpins (Cottus). In these we have identified species that have recently (<200 years) hybridized as a result of secondary contact through man-made canals between river systems. This gave rise to a new lineage with new adaptations that have allowed it to invade habitats that were not used by the parental species before. We are thus also dealing with evolutionary change that is associated with man-made ecological perturbations, the analysis of which is particularly timely. It is now possible to perform a near exhaustive search to identify genes and to study gene expression as a measure of evolutionary change in Cottus. A combination of genetic mapping experiments and screens for genotypic selection can reveal loci and functions as targets of selection in the adaptive evolution of invasive Cottus. This proposal specifically aims at identifying genomic traits such as copy number changes of coding sequences or changes in the gene regulatory architecture that have evolved as a direct consequence of hybridization and to explore their implication in adaptive evolution. The results will contribute to our understanding of the genetics of adaptation and the invasion of a new environment. With respect to hybrid zones and the evolution of new species, we will identify candidate genes and functions that can explain barriers to reproduction in the wild. Finally, we will be able to make significant progress with respect to the genetics associated with hybrid speciation.
Summary
It is the unprecedented access to genome wide data that highlights the potential of current evolutionary studies and this proposal aims at exploiting this progress to analyze evolutionary processes in a well-established fish system of hybrid speciation. We study natural populations of freshwater fish referred to as sculpins (Cottus). In these we have identified species that have recently (<200 years) hybridized as a result of secondary contact through man-made canals between river systems. This gave rise to a new lineage with new adaptations that have allowed it to invade habitats that were not used by the parental species before. We are thus also dealing with evolutionary change that is associated with man-made ecological perturbations, the analysis of which is particularly timely. It is now possible to perform a near exhaustive search to identify genes and to study gene expression as a measure of evolutionary change in Cottus. A combination of genetic mapping experiments and screens for genotypic selection can reveal loci and functions as targets of selection in the adaptive evolution of invasive Cottus. This proposal specifically aims at identifying genomic traits such as copy number changes of coding sequences or changes in the gene regulatory architecture that have evolved as a direct consequence of hybridization and to explore their implication in adaptive evolution. The results will contribute to our understanding of the genetics of adaptation and the invasion of a new environment. With respect to hybrid zones and the evolution of new species, we will identify candidate genes and functions that can explain barriers to reproduction in the wild. Finally, we will be able to make significant progress with respect to the genetics associated with hybrid speciation.
Max ERC Funding
1 377 162 €
Duration
Start date: 2014-02-01, End date: 2019-01-31
