Project acronym BIOCCORA
Project Full biomechanical characterization of the coronary atherosclerotic plaque: biomechanics meets imaging
Researcher (PI) Jolanda Wentzel
Host Institution (HI) ERASMUS UNIVERSITAIR MEDISCH CENTRUM ROTTERDAM
Call Details Starting Grant (StG), LS7, ERC-2012-StG_20111109
Summary Myocardial infarction is responsible for nearly 40% of the mortality in the western world and is mainly triggered by rupture of vulnerable atherosclerotic plaques in the coronary arteries. Biomechanical parameters play a major role in the generation and rupture of vulnerable plaques. I was the first to show the relationship between shear stress – one of the biomechanical parameters - and plaque formation in human coronary arteries in vivo. This accomplishment was achieved by the development of a new 3D reconstruction technique for (human) coronary arteries in vivo. This reconstruction technique allowed assessment of shear stress by computational fluid dynamics and thereby opened new avenues for serial studies on the role of biomechanical parameters in cardiovascular disease. However, these reconstructions lack information on the vessel wall composition, which is essential for stress computations in the vessel wall. Recent developments in intravascular image technologies allow visualization of one or more of the different plaque components. Therefore, advances in image fusion are required to merge the different plaque components into one single 3D vulnerable plaque reconstruction. I will go beyond the state-of-the art in image based modeling by developing novel technology to 3D reconstruct coronary lumen and vessel wall, including plaque composition and assess biomechanical tissue properties allowing for full biomechanical characterization (shear stress and wall stress) of the coronary plaque. The developed technology will be applied to study 1) vulnerable plaque progression, destabilization and rupture, to improve identification of risk on myocardial infarction and 2) predicting treatment outcome of stent implantation by simulating stent deployment, thereby opening a whole new direction in cardiovascular research.
Summary
Myocardial infarction is responsible for nearly 40% of the mortality in the western world and is mainly triggered by rupture of vulnerable atherosclerotic plaques in the coronary arteries. Biomechanical parameters play a major role in the generation and rupture of vulnerable plaques. I was the first to show the relationship between shear stress – one of the biomechanical parameters - and plaque formation in human coronary arteries in vivo. This accomplishment was achieved by the development of a new 3D reconstruction technique for (human) coronary arteries in vivo. This reconstruction technique allowed assessment of shear stress by computational fluid dynamics and thereby opened new avenues for serial studies on the role of biomechanical parameters in cardiovascular disease. However, these reconstructions lack information on the vessel wall composition, which is essential for stress computations in the vessel wall. Recent developments in intravascular image technologies allow visualization of one or more of the different plaque components. Therefore, advances in image fusion are required to merge the different plaque components into one single 3D vulnerable plaque reconstruction. I will go beyond the state-of-the art in image based modeling by developing novel technology to 3D reconstruct coronary lumen and vessel wall, including plaque composition and assess biomechanical tissue properties allowing for full biomechanical characterization (shear stress and wall stress) of the coronary plaque. The developed technology will be applied to study 1) vulnerable plaque progression, destabilization and rupture, to improve identification of risk on myocardial infarction and 2) predicting treatment outcome of stent implantation by simulating stent deployment, thereby opening a whole new direction in cardiovascular research.
Max ERC Funding
1 877 000 €
Duration
Start date: 2013-05-01, End date: 2019-04-30
Project acronym BIOMECHTOOLS
Project Biomechanical diagnostic, pre-planning and outcome tools to improve musculoskeletal surgery
Researcher (PI) Nicolaas Verdonschot
Host Institution (HI) STICHTING KATHOLIEKE UNIVERSITEIT
Call Details Advanced Grant (AdG), LS7, ERC-2012-ADG_20120314
Summary The aetiology of many musculoskeletal (MS) diseases is related to biomechanical factors. However, the tools to assess the biomechanical condition of patients used by clinicians and researchers are often crude and subjective leading to non-optimal patient analyses and care. In this project innovations related to imaging, sensor technology and biomechanical modelling are utilized to generate versatile, accurate and objective methods to quantify the (pathological) MS condition of the lower extremity of patients in a unique manner. The project will produce advanced diagnostic, pre-planning and outcome tools which allow clinicians and researchers for detailed biomechanical analysis about abnormal tissue deformations, pathological loading of the joints, abnormal stresses in the hard and soft tissues, and aberrant joint kinematics.
The key objectives of this proposal are:
1) Develop and validate image-based 3-D volumetric elastographic diagnostic methods that can quantify normal and pathological conditions under dynamic loading and which can be linked to biomechanical modelling tools.
2) Create an ultrasound (US)-based system to assess internal joint kinematics which can be used as a diagnostic tool for clinicians and researchers and is a validation tool for biomechanical modelling.
3) Generate and validate an ambulant functional (force and kinematic) diagnostic system which is easy to use and which can be used to provide input data for biomechanical models.
4) Create and validate a new modelling approach that integrates muscle-models with finite element models at a highly personalized level.
5) Generate biomechanical models which have personalized mechanical properties of the hard and soft tissues.
6) Demonstrate the applicability of the personalized diagnostic and pre-planning platform by application to healthy individuals and patient subjects.
Support from the ERC will open new research fields related to biomechanical patient assessment and modeling of MS pathologies.
Summary
The aetiology of many musculoskeletal (MS) diseases is related to biomechanical factors. However, the tools to assess the biomechanical condition of patients used by clinicians and researchers are often crude and subjective leading to non-optimal patient analyses and care. In this project innovations related to imaging, sensor technology and biomechanical modelling are utilized to generate versatile, accurate and objective methods to quantify the (pathological) MS condition of the lower extremity of patients in a unique manner. The project will produce advanced diagnostic, pre-planning and outcome tools which allow clinicians and researchers for detailed biomechanical analysis about abnormal tissue deformations, pathological loading of the joints, abnormal stresses in the hard and soft tissues, and aberrant joint kinematics.
The key objectives of this proposal are:
1) Develop and validate image-based 3-D volumetric elastographic diagnostic methods that can quantify normal and pathological conditions under dynamic loading and which can be linked to biomechanical modelling tools.
2) Create an ultrasound (US)-based system to assess internal joint kinematics which can be used as a diagnostic tool for clinicians and researchers and is a validation tool for biomechanical modelling.
3) Generate and validate an ambulant functional (force and kinematic) diagnostic system which is easy to use and which can be used to provide input data for biomechanical models.
4) Create and validate a new modelling approach that integrates muscle-models with finite element models at a highly personalized level.
5) Generate biomechanical models which have personalized mechanical properties of the hard and soft tissues.
6) Demonstrate the applicability of the personalized diagnostic and pre-planning platform by application to healthy individuals and patient subjects.
Support from the ERC will open new research fields related to biomechanical patient assessment and modeling of MS pathologies.
Max ERC Funding
2 456 400 €
Duration
Start date: 2013-05-01, End date: 2018-04-30
Project acronym CALMIRS
Project RNA-based regulation of signal transduction –
Regulation of calcineurin/NFAT signaling by microRNA-based mechanisms
Researcher (PI) Leon Johannes De Windt
Host Institution (HI) UNIVERSITEIT MAASTRICHT
Call Details Starting Grant (StG), LS4, ERC-2012-StG_20111109
Summary "Heart failure is a serious clinical disorder that represents the primary cause of hospitalization and death in Europe and the United States. There is a dire need for new paradigms and therapeutic approaches for treatment of this devastating disease. The heart responds to mechanical load and various extracellular stimuli by hypertrophic growth and sustained pathological hypertrophy is a major clinical predictor of heart failure. A variety of stress-responsive signaling pathways promote cardiac hypertrophy, but the precise mechanisms that link these pathways to cardiac disease are only beginning to be unveiled. Signal transduction is traditionally concentrated on the protein coding part of the genome, but it is now appreciated that the protein coding part of the genome only constitutes 1.5% of the genome. RNA based mechanisms may provide a more complete understanding of the fundamentals of cellular signaling. As a proof-of-principle, we focus on a principal hypertrophic signaling cascade, cardiac calcineurin/NFAT signaling. Here we will establish that microRNAs are intimately interwoven with this signaling cascade, influence signaling strength by unexpected upstream mechanisms. Secondly, we will firmly establish that microRNA target genes critically contribute to genesis of heart failure. Third, the surprising stability of circulating microRNAs has opened the possibility to develop the next generation of biomarkers and provide unexpected mechanisms how genetic information is transported between cells in multicellular organs and fascilitate inter-cellular communication. Finally, microRNA-based therapeutic silencing is remarkably powerful and offers opportunities to specifically intervene in pathological signaling as the next generation heart failure therapeutics. CALMIRS aims to mine the wealth of these RNA mechanisms to enable the development of next generation RNA based signal transduction biology, with surprising new diagnostic and therapeutic opportunities."
Summary
"Heart failure is a serious clinical disorder that represents the primary cause of hospitalization and death in Europe and the United States. There is a dire need for new paradigms and therapeutic approaches for treatment of this devastating disease. The heart responds to mechanical load and various extracellular stimuli by hypertrophic growth and sustained pathological hypertrophy is a major clinical predictor of heart failure. A variety of stress-responsive signaling pathways promote cardiac hypertrophy, but the precise mechanisms that link these pathways to cardiac disease are only beginning to be unveiled. Signal transduction is traditionally concentrated on the protein coding part of the genome, but it is now appreciated that the protein coding part of the genome only constitutes 1.5% of the genome. RNA based mechanisms may provide a more complete understanding of the fundamentals of cellular signaling. As a proof-of-principle, we focus on a principal hypertrophic signaling cascade, cardiac calcineurin/NFAT signaling. Here we will establish that microRNAs are intimately interwoven with this signaling cascade, influence signaling strength by unexpected upstream mechanisms. Secondly, we will firmly establish that microRNA target genes critically contribute to genesis of heart failure. Third, the surprising stability of circulating microRNAs has opened the possibility to develop the next generation of biomarkers and provide unexpected mechanisms how genetic information is transported between cells in multicellular organs and fascilitate inter-cellular communication. Finally, microRNA-based therapeutic silencing is remarkably powerful and offers opportunities to specifically intervene in pathological signaling as the next generation heart failure therapeutics. CALMIRS aims to mine the wealth of these RNA mechanisms to enable the development of next generation RNA based signal transduction biology, with surprising new diagnostic and therapeutic opportunities."
Max ERC Funding
1 499 528 €
Duration
Start date: 2013-02-01, End date: 2018-01-31
Project acronym CD-LINK
Project Celiac disease: from lincRNAs to disease mechanism
Researcher (PI) Tjitske Nienke Wijmenga
Host Institution (HI) ACADEMISCH ZIEKENHUIS GRONINGEN
Call Details Advanced Grant (AdG), LS2, ERC-2012-ADG_20120314
Summary Celiac disease affects at least 1% of the world population. Its onset is triggered by gluten, a common dietary protein, however, its etiology is poorly understood. More than 80% of patients are not properly diagnosed and they therefore do not follow a gluten-free diet, thereby increasing their risk for disease-associated complications and early death. A better understanding of the disease biology would improve the diagnosis, prevention, and treatment of celiac disease.
This project investigates the disease mechanisms in celiac disease by using predisposing genes and genetic variants as disease initiating factors. Specifically, it will investigate if long, intergenic non-coding RNAs (lincRNAs) are causally involved in celiac disease pathogenesis by regulating protein-coding genes and pathways associated with the disease.
This project is based on two important observations by my group: (1) Our genetic studies, which led to identifying 39 celiac disease risk loci, suggest that the mechanism underlying the disease is largely governed by dysregulation of gene expression. (2) We uncovered a previously unrecognized role for lincRNAs that provides clues as to exactly how genetic variation causes disease, as this class of biologically important RNA molecules regulate gene expression.
The research will be performed in CD4+ T cells, a severely affected cell type in disease pathology. I will first use celiac disease-associated protein-coding genes to delineate their regulatory pathways and then study the transcriptional programs of lincRNAs present in celiac disease loci. Next I will combine the information and investigate if the expressed lincRNAs modulate the pathways and affect T cell function, thereby discovering if lincRNAs are a missing link between non-coding genetic variation and protein-coding genes. Our findings may well lead to potential therapeutic targets and provide a solid scientific basis for new diagnostic markers, particularly biomarkers, based on genetics.
Summary
Celiac disease affects at least 1% of the world population. Its onset is triggered by gluten, a common dietary protein, however, its etiology is poorly understood. More than 80% of patients are not properly diagnosed and they therefore do not follow a gluten-free diet, thereby increasing their risk for disease-associated complications and early death. A better understanding of the disease biology would improve the diagnosis, prevention, and treatment of celiac disease.
This project investigates the disease mechanisms in celiac disease by using predisposing genes and genetic variants as disease initiating factors. Specifically, it will investigate if long, intergenic non-coding RNAs (lincRNAs) are causally involved in celiac disease pathogenesis by regulating protein-coding genes and pathways associated with the disease.
This project is based on two important observations by my group: (1) Our genetic studies, which led to identifying 39 celiac disease risk loci, suggest that the mechanism underlying the disease is largely governed by dysregulation of gene expression. (2) We uncovered a previously unrecognized role for lincRNAs that provides clues as to exactly how genetic variation causes disease, as this class of biologically important RNA molecules regulate gene expression.
The research will be performed in CD4+ T cells, a severely affected cell type in disease pathology. I will first use celiac disease-associated protein-coding genes to delineate their regulatory pathways and then study the transcriptional programs of lincRNAs present in celiac disease loci. Next I will combine the information and investigate if the expressed lincRNAs modulate the pathways and affect T cell function, thereby discovering if lincRNAs are a missing link between non-coding genetic variation and protein-coding genes. Our findings may well lead to potential therapeutic targets and provide a solid scientific basis for new diagnostic markers, particularly biomarkers, based on genetics.
Max ERC Funding
2 319 914 €
Duration
Start date: 2013-02-01, End date: 2018-11-30
Project acronym DCVFUSION
Project Telling the full story: how neurons send other signals than by classical synaptic transmission
Researcher (PI) Matthijs Verhage
Host Institution (HI) STICHTING VUMC
Call Details Advanced Grant (AdG), LS5, ERC-2012-ADG_20120314
Summary The regulated secretion of chemical signals in the brain occurs principally from two organelles, synaptic vesicles and dense core vesicles (DCVs). Synaptic vesicle secretion accounts for the well characterized local, fast signalling in synapses. DCVs contain a diverse collection of cargo, including many neuropeptides that trigger a multitude of modulatory effects with quite robust impact, for instance on memory, mood, pain, appetite or social behavior. Disregulation of neuropeptide secretion is firmly associated with many diseases such as cognitive and mood disorders, obesity and diabetes. In addition, many other signals depend on DCVs, for instance trophic factors and proteolytic enzymes, but also signals that typically do not diffuse like guidance cues and pre-assembled active zones. Hence, it is beyond doubt that DCV signalling is a central factor in brain communication. However, many fundamental questions remain open on DCV trafficking and secretion. Therefore, the aim of this proposal is to characterize the molecular principles that account for DCV delivery at release sites and their secretion. I will address 4 fundamental questions: What are the molecular factors that drive DCV fusion in mammalian CNS neurons? How does Ca2+ trigger DCV fusion? What are the requirements of DCV release sites and where do they occur? Can DCV fusion be targeted to synthetic release sites in vivo? I will exploit >30 mutant mouse lines and new cell biological and photonic approaches that allow for the first time a quantitative assessment of DCV-trafficking and fusion of many cargo types, in living neurons with a single vesicle resolution. Preliminary data suggest that DCV secretion is quite different from synaptic vesicle and chromaffin granule secretion. Together, these studies will produce the first systematic evaluation of the molecular identity of the core machinery that drives DCV fusion in neurons, the Ca2+-affinity of DCV fusion and the characteristics of DCV release sites.
Summary
The regulated secretion of chemical signals in the brain occurs principally from two organelles, synaptic vesicles and dense core vesicles (DCVs). Synaptic vesicle secretion accounts for the well characterized local, fast signalling in synapses. DCVs contain a diverse collection of cargo, including many neuropeptides that trigger a multitude of modulatory effects with quite robust impact, for instance on memory, mood, pain, appetite or social behavior. Disregulation of neuropeptide secretion is firmly associated with many diseases such as cognitive and mood disorders, obesity and diabetes. In addition, many other signals depend on DCVs, for instance trophic factors and proteolytic enzymes, but also signals that typically do not diffuse like guidance cues and pre-assembled active zones. Hence, it is beyond doubt that DCV signalling is a central factor in brain communication. However, many fundamental questions remain open on DCV trafficking and secretion. Therefore, the aim of this proposal is to characterize the molecular principles that account for DCV delivery at release sites and their secretion. I will address 4 fundamental questions: What are the molecular factors that drive DCV fusion in mammalian CNS neurons? How does Ca2+ trigger DCV fusion? What are the requirements of DCV release sites and where do they occur? Can DCV fusion be targeted to synthetic release sites in vivo? I will exploit >30 mutant mouse lines and new cell biological and photonic approaches that allow for the first time a quantitative assessment of DCV-trafficking and fusion of many cargo types, in living neurons with a single vesicle resolution. Preliminary data suggest that DCV secretion is quite different from synaptic vesicle and chromaffin granule secretion. Together, these studies will produce the first systematic evaluation of the molecular identity of the core machinery that drives DCV fusion in neurons, the Ca2+-affinity of DCV fusion and the characteristics of DCV release sites.
Max ERC Funding
2 439 315 €
Duration
Start date: 2013-05-01, End date: 2019-04-30
Project acronym DECODINGSUMO
Project Cracking the SUMO Signalling Code
Researcher (PI) Alfredus Cornelis Otto Vertegaal
Host Institution (HI) ACADEMISCH ZIEKENHUIS LEIDEN
Call Details Starting Grant (StG), LS1, ERC-2012-StG_20111109
Summary "Functional activity of proteins is tightly controlled via reversible post-translational modifications including phosphorylation, acetylation and ubiquitylation. These modifications enable the orchestration of cellular responses to a wide variety of stimuli. Due to these modifications, proteomes are overwhelmingly complex. Progress in the field has been greatly accelerated by the development of novel approaches to study these post-translational modifications at a proteome-wide scale using the sensitivity and robustness of mass spectrometry (MS). This has enabled the identification of thousands of dynamically regulated phosphorylation, acetylation and ubiquitylation sites by MS. The functional significance of these modifications is now being addressed worldwide at an unprecedented scale. In contrast, global understanding of ubiquitin-like signalling networks in a site-specific manner is very challenging.
Over the last few years, my lab has established novel methodology for the purification and identification of endogenous SUMO target proteins and SUMOylation sites of endogenous targets. The first aim of this project is to uncover small ubiquitin-like modifier (SUMO) signalling pathways in a site-specific manner at a proteome-wide level.
The second aim of this project is to reveal how SUMOylation cooperates with ubiquitylation to maintain genome integrity. SUMOylation plays a critical role during the DNA damage response, an important barrier against genome instability linked diseases including cancer and neurodegeneration. Selected target proteins will be studied at the functional and mechanistic level to obtain novel insight in cellular processes that protect against genome instability.
The developed methodology is generic and can be applied to study all ubiquitin-like proteins at a proteome-wide level in a site-specific manner, enabling global understanding of ubiquitin-like signalling networks in health and disease."
Summary
"Functional activity of proteins is tightly controlled via reversible post-translational modifications including phosphorylation, acetylation and ubiquitylation. These modifications enable the orchestration of cellular responses to a wide variety of stimuli. Due to these modifications, proteomes are overwhelmingly complex. Progress in the field has been greatly accelerated by the development of novel approaches to study these post-translational modifications at a proteome-wide scale using the sensitivity and robustness of mass spectrometry (MS). This has enabled the identification of thousands of dynamically regulated phosphorylation, acetylation and ubiquitylation sites by MS. The functional significance of these modifications is now being addressed worldwide at an unprecedented scale. In contrast, global understanding of ubiquitin-like signalling networks in a site-specific manner is very challenging.
Over the last few years, my lab has established novel methodology for the purification and identification of endogenous SUMO target proteins and SUMOylation sites of endogenous targets. The first aim of this project is to uncover small ubiquitin-like modifier (SUMO) signalling pathways in a site-specific manner at a proteome-wide level.
The second aim of this project is to reveal how SUMOylation cooperates with ubiquitylation to maintain genome integrity. SUMOylation plays a critical role during the DNA damage response, an important barrier against genome instability linked diseases including cancer and neurodegeneration. Selected target proteins will be studied at the functional and mechanistic level to obtain novel insight in cellular processes that protect against genome instability.
The developed methodology is generic and can be applied to study all ubiquitin-like proteins at a proteome-wide level in a site-specific manner, enabling global understanding of ubiquitin-like signalling networks in health and disease."
Max ERC Funding
1 517 699 €
Duration
Start date: 2013-01-01, End date: 2017-12-31
Project acronym DustTraffic
Project Transatlantic fluxes of Saharan dust: changing climate through fertilising the ocean?
Researcher (PI) Jan-Berend Willem Stuut
Host Institution (HI) STICHTING NIOZ, KONINKLIJK NEDERLANDS INSTITUUT VOOR ONDERZOEK DER ZEE
Call Details Starting Grant (StG), LS9, ERC-2012-StG_20111109
Summary Massive amounts of dust (~1 Billion Ton) are blown from the Sahara into and over the Atlantic Ocean every year. This dust strongly alters the atmosphere through blocking incoming solar radiation [cooling the atmosphere] and trapping outgoing heat that was reflected at the earth’s surface [warming the atmosphere]. In addition, aerosols carry huge amounts of metals and nutrients that can boost marine life, but also vast amounts of microbes, spores, and pathogens that are harmful for both marine- and terrestrial (including human!) life. The net effect of cooling/warming and ocean fertilisation/poisoning is presently far from understood as it depends on a complex set of parameters related to dust emission, dispersal, and deposition. In order to quantify these parameters, I propose to develop and apply a novel approach to study the transatlantic flux of Saharan dust and its environmental effect on the ocean by deploying a transect of seven ocean moorings with a dust-collecting surface buoy below the Saharan dust plume from NW Africa to the Caribbean. Sampling dust in air as well as under water at a biweekly resolution for initially one complete year will for the first time allow to: 1) quantify the seasonal variability in Saharan dust export into the Atlantic, 2) distinguish between high-altitude summer plumes versus low-level winter trade-wind transport, 3) quantify source-to-sink changes in particle size and the related (metal, nutrient, and biological-) composition of the dust, and 4) determine the in situ bio-availability of the associated nutrients and their potential fertilisation of the photic zone. These unique, seasonally and spatially resolved data will bridge the gap between the bi-weekly sediment-trap record off Cape Blanc (NW Africa, since '85) and the daily dust fluxes recorded on Barbados (Caribbean, since '73). Subsequently, the data can be extrapolated back in time in marine sediments, which are an archive for dust transport and carbon pump in the past.
Summary
Massive amounts of dust (~1 Billion Ton) are blown from the Sahara into and over the Atlantic Ocean every year. This dust strongly alters the atmosphere through blocking incoming solar radiation [cooling the atmosphere] and trapping outgoing heat that was reflected at the earth’s surface [warming the atmosphere]. In addition, aerosols carry huge amounts of metals and nutrients that can boost marine life, but also vast amounts of microbes, spores, and pathogens that are harmful for both marine- and terrestrial (including human!) life. The net effect of cooling/warming and ocean fertilisation/poisoning is presently far from understood as it depends on a complex set of parameters related to dust emission, dispersal, and deposition. In order to quantify these parameters, I propose to develop and apply a novel approach to study the transatlantic flux of Saharan dust and its environmental effect on the ocean by deploying a transect of seven ocean moorings with a dust-collecting surface buoy below the Saharan dust plume from NW Africa to the Caribbean. Sampling dust in air as well as under water at a biweekly resolution for initially one complete year will for the first time allow to: 1) quantify the seasonal variability in Saharan dust export into the Atlantic, 2) distinguish between high-altitude summer plumes versus low-level winter trade-wind transport, 3) quantify source-to-sink changes in particle size and the related (metal, nutrient, and biological-) composition of the dust, and 4) determine the in situ bio-availability of the associated nutrients and their potential fertilisation of the photic zone. These unique, seasonally and spatially resolved data will bridge the gap between the bi-weekly sediment-trap record off Cape Blanc (NW Africa, since '85) and the daily dust fluxes recorded on Barbados (Caribbean, since '73). Subsequently, the data can be extrapolated back in time in marine sediments, which are an archive for dust transport and carbon pump in the past.
Max ERC Funding
1 972 839 €
Duration
Start date: 2012-10-01, End date: 2017-09-30
Project acronym DynGenome
Project The Dynamics of Genome Processing
Researcher (PI) Nynke Dekker
Host Institution (HI) TECHNISCHE UNIVERSITEIT DELFT
Call Details Starting Grant (StG), LS1, ERC-2012-StG_20111109
Summary The vast quantity of information in our genomes must continuously be read out and processed. This is done by proteins, acting either individually or as part of larger protein complexes. How this genome processing operates successfully, given the crowded nature of the DNA track as well as its mechanical constraints and coiling, is a question of fundamental interest.
We will investigate the dynamics of genome processing during DNA transcription and replication. Throughout, we ask the question, what brings these processes to a halt? Focusing on both individual molecular motors and protein complexes, we ask, when do these stall? Both mechanical constraints such as the accumulation of torsional stress and the presence of proteins along the DNA helix may conspire, intentionally or not, to halt transcription and replication.
Specifically, we will investigate how RNA polymerases, replicative helicases, and replisomes can be derailed or stalled. These experiments will shed light on the mechanochemical cycle of RNA polymerase, on its motion along a complex track, on the physical interactions that occur between helicases and proteins at termination, and on replisome dynamics near stall. They will also quantify the effects of torsional stress in DNA on the advancement of transcription and replication.
The proteins and protein complexes studied here include principal actors in processes essential to cell survival. Understanding the manners in which they can fail will illuminate their mechanism and cellular roles. The powerful single-molecule instrumentation that we have developed in recent years allows one to visualize individual proteins while precisely controlling and monitoring the state of DNA. When harnessed to answer these profound biological questions, we extend not only our knowledge of biological processes but also our understanding of how simple physical principles can govern a wide range of phenomena, thereby having an impact on biology and physics alike.
Summary
The vast quantity of information in our genomes must continuously be read out and processed. This is done by proteins, acting either individually or as part of larger protein complexes. How this genome processing operates successfully, given the crowded nature of the DNA track as well as its mechanical constraints and coiling, is a question of fundamental interest.
We will investigate the dynamics of genome processing during DNA transcription and replication. Throughout, we ask the question, what brings these processes to a halt? Focusing on both individual molecular motors and protein complexes, we ask, when do these stall? Both mechanical constraints such as the accumulation of torsional stress and the presence of proteins along the DNA helix may conspire, intentionally or not, to halt transcription and replication.
Specifically, we will investigate how RNA polymerases, replicative helicases, and replisomes can be derailed or stalled. These experiments will shed light on the mechanochemical cycle of RNA polymerase, on its motion along a complex track, on the physical interactions that occur between helicases and proteins at termination, and on replisome dynamics near stall. They will also quantify the effects of torsional stress in DNA on the advancement of transcription and replication.
The proteins and protein complexes studied here include principal actors in processes essential to cell survival. Understanding the manners in which they can fail will illuminate their mechanism and cellular roles. The powerful single-molecule instrumentation that we have developed in recent years allows one to visualize individual proteins while precisely controlling and monitoring the state of DNA. When harnessed to answer these profound biological questions, we extend not only our knowledge of biological processes but also our understanding of how simple physical principles can govern a wide range of phenomena, thereby having an impact on biology and physics alike.
Max ERC Funding
1 500 000 €
Duration
Start date: 2013-01-01, End date: 2017-12-31
Project acronym ECOEVODEVO
Project Eco-evolutionary dynamics of community self-organization through ontogenetic asymmetry
Researcher (PI) Andre Marc De Roos
Host Institution (HI) UNIVERSITEIT VAN AMSTERDAM
Call Details Advanced Grant (AdG), LS8, ERC-2012-ADG_20120314
Summary Classical theory on community ecology models dynamics as interplay between top-down and bottom-up effects of population abundances only and considers population composition irrelevant. It ignores food-dependent ontogenetic development, in particular somatic growth, which characterizes most species and uniquely distinguishes organisms from fundamental units in physical or chemical multi-particle systems. Similarly, evolutionary theory has ignored the potential population feedback on food-dependent ontogenetic development. Classic theory has been shown to apply in case of ontogenetic symmetry in energetics, when dynamics of population abundance and composition are independent. Ontogenetic symmetry stipulates that mass-specific rates of net biomass turnover are independent of individual body size. Ontogenetic symmetry only represents a limiting, structurally unstable case, separating two stable domains with ontogenetic asymmetry in energetics, when either juveniles or adults have higher mass-specific net-biomass production. In case of ontogenetic asymmetry the dynamics of population abundance and composition become intimately linked, ultimately resulting in the emergence of positive feedbacks between densities of predators and their main prey. This transforms consumer-resource interactions into indivisible units, whose behavior can no longer be predicted from its constituting parts (the species). Ontogenetic asymmetry in energetics is thus a potent driver of self-organization in ecological communities. This research project aims at unraveling the eco-evolutionary dynamics of ontogenetic asymmetry in energetics, focusing on (1) the likelihood that ontogenetic asymmetry in energetics evolves as mechanism of self-organization in ecological communities, (2) the conditions that may have promoted or inhibited this evolution and (3) the extent to which ontogenetic asymmetry in energetics has contributed to the diversity of life and the development of complex life cycles.
Summary
Classical theory on community ecology models dynamics as interplay between top-down and bottom-up effects of population abundances only and considers population composition irrelevant. It ignores food-dependent ontogenetic development, in particular somatic growth, which characterizes most species and uniquely distinguishes organisms from fundamental units in physical or chemical multi-particle systems. Similarly, evolutionary theory has ignored the potential population feedback on food-dependent ontogenetic development. Classic theory has been shown to apply in case of ontogenetic symmetry in energetics, when dynamics of population abundance and composition are independent. Ontogenetic symmetry stipulates that mass-specific rates of net biomass turnover are independent of individual body size. Ontogenetic symmetry only represents a limiting, structurally unstable case, separating two stable domains with ontogenetic asymmetry in energetics, when either juveniles or adults have higher mass-specific net-biomass production. In case of ontogenetic asymmetry the dynamics of population abundance and composition become intimately linked, ultimately resulting in the emergence of positive feedbacks between densities of predators and their main prey. This transforms consumer-resource interactions into indivisible units, whose behavior can no longer be predicted from its constituting parts (the species). Ontogenetic asymmetry in energetics is thus a potent driver of self-organization in ecological communities. This research project aims at unraveling the eco-evolutionary dynamics of ontogenetic asymmetry in energetics, focusing on (1) the likelihood that ontogenetic asymmetry in energetics evolves as mechanism of self-organization in ecological communities, (2) the conditions that may have promoted or inhibited this evolution and (3) the extent to which ontogenetic asymmetry in energetics has contributed to the diversity of life and the development of complex life cycles.
Max ERC Funding
1 779 634 €
Duration
Start date: 2013-06-01, End date: 2018-05-31
Project acronym enhReg
Project Exploring enhancers’ Achilles Heel
Researcher (PI) Reuven Agami
Host Institution (HI) STICHTING HET NEDERLANDS KANKER INSTITUUT-ANTONI VAN LEEUWENHOEK ZIEKENHUIS
Call Details Advanced Grant (AdG), LS2, ERC-2012-ADG_20120314
Summary Enhancers are genomic domains that regulate transcription of distantly located genes and that are characterized by specific chromatin signatures of histone methylation and acetylation patterns. Interestingly, RNA polymerase II (RNAPII) binds to a subset of enhancers and produces transcripts, called enhancer RNAs (eRNAs). These are produced bi-directionally and, in contrast to mRNAs and many other non-coding RNAs, are not polyadenylated. Generally, the transcription of eRNAs was shown to positively correlate with mRNA levels of surrounding protein-coding genes. However, it is unclear if eRNAs carry a transcriptional function.
p53 is a transcription factor and tumor suppressor that is very frequently mutated in cancer. Chromatin-binding profiles reveal specific interactions of p53 with promoter regions of nearby genes, within genes, but also with remote regions located more than 50 kbps away from any known gene. Interestingly, many of these remote regions possess evolutionary highly conserved p53-binding sites and all known hallmarks of enhancer regions, as well as binding of RNAPII. We found out that many remote p53-bound domains are indeed p53-dependent eRNA-producing enhancers, and, most importantly, eRNA production was required for transcriptional induction of distal genes and for p53-dependent cellular control.
Here we will:
1. Investigate in detail the mechanism of action and function of p53-dependent eRNAs.
2. Expand studies to identify eRNAs with oncogenic function.
3. Develop efficient ways to target eRNAs.
4. Target eRNAs and study their capacity to inhibit tumorigenicity.
As eRNAs are mediators of enhancer activity with sequence specific content and sensitivity to siRNA targeting, they might be the Achilles heel through which oncogenic enhancer activity could be suppressed. Our study will elucidate a novel layer of gene regulation and holds promise for opening up new opportunities to affect cancer-related cellular programs in very specific and effectiv
Summary
Enhancers are genomic domains that regulate transcription of distantly located genes and that are characterized by specific chromatin signatures of histone methylation and acetylation patterns. Interestingly, RNA polymerase II (RNAPII) binds to a subset of enhancers and produces transcripts, called enhancer RNAs (eRNAs). These are produced bi-directionally and, in contrast to mRNAs and many other non-coding RNAs, are not polyadenylated. Generally, the transcription of eRNAs was shown to positively correlate with mRNA levels of surrounding protein-coding genes. However, it is unclear if eRNAs carry a transcriptional function.
p53 is a transcription factor and tumor suppressor that is very frequently mutated in cancer. Chromatin-binding profiles reveal specific interactions of p53 with promoter regions of nearby genes, within genes, but also with remote regions located more than 50 kbps away from any known gene. Interestingly, many of these remote regions possess evolutionary highly conserved p53-binding sites and all known hallmarks of enhancer regions, as well as binding of RNAPII. We found out that many remote p53-bound domains are indeed p53-dependent eRNA-producing enhancers, and, most importantly, eRNA production was required for transcriptional induction of distal genes and for p53-dependent cellular control.
Here we will:
1. Investigate in detail the mechanism of action and function of p53-dependent eRNAs.
2. Expand studies to identify eRNAs with oncogenic function.
3. Develop efficient ways to target eRNAs.
4. Target eRNAs and study their capacity to inhibit tumorigenicity.
As eRNAs are mediators of enhancer activity with sequence specific content and sensitivity to siRNA targeting, they might be the Achilles heel through which oncogenic enhancer activity could be suppressed. Our study will elucidate a novel layer of gene regulation and holds promise for opening up new opportunities to affect cancer-related cellular programs in very specific and effectiv
Max ERC Funding
2 176 840 €
Duration
Start date: 2013-10-01, End date: 2018-09-30