Project acronym 20SComplexity
Project An integrative approach to uncover the multilevel regulation of 20S proteasome degradation
Researcher (PI) Michal Sharon
Host Institution (HI) WEIZMANN INSTITUTE OF SCIENCE
Country Israel
Call Details Starting Grant (StG), LS1, ERC-2014-STG
Summary For many years, the ubiquitin-26S proteasome degradation pathway was considered the primary route for proteasomal degradation. However, it is now becoming clear that proteins can also be targeted for degradation by a ubiquitin-independent mechanism mediated by the core 20S proteasome itself. Although initially believed to be limited to rare exceptions, degradation by the 20S proteasome is now understood to have a wide range of substrates, many of which are key regulatory proteins. Despite its importance, little is known about the mechanisms that control 20S proteasomal degradation, unlike the extensive knowledge acquired over the years concerning degradation by the 26S proteasome. Our overall aim is to reveal the multiple regulatory levels that coordinate the 20S proteasome degradation route.
To achieve this goal we will carry out a comprehensive research program characterizing three distinct levels of 20S proteasome regulation:
Intra-molecular regulation- Revealing the intrinsic molecular switch that activates the latent 20S proteasome.
Inter-molecular regulation- Identifying novel proteins that bind the 20S proteasome to regulate its activity and characterizing their mechanism of function.
Cellular regulatory networks- Unraveling the cellular cues and multiple pathways that influence 20S proteasome activity using a novel systematic and unbiased screening approach.
Our experimental strategy involves the combination of biochemical approaches with native mass spectrometry, cross-linking and fluorescence measurements, complemented by cell biology analyses and high-throughput screening. Such a multidisciplinary approach, integrating in vitro and in vivo findings, will likely provide the much needed knowledge on the 20S proteasome degradation route. When completed, we anticipate that this work will be part of a new paradigm – no longer perceiving the 20S proteasome mediated degradation as a simple and passive event but rather a tightly regulated and coordinated process.
Summary
For many years, the ubiquitin-26S proteasome degradation pathway was considered the primary route for proteasomal degradation. However, it is now becoming clear that proteins can also be targeted for degradation by a ubiquitin-independent mechanism mediated by the core 20S proteasome itself. Although initially believed to be limited to rare exceptions, degradation by the 20S proteasome is now understood to have a wide range of substrates, many of which are key regulatory proteins. Despite its importance, little is known about the mechanisms that control 20S proteasomal degradation, unlike the extensive knowledge acquired over the years concerning degradation by the 26S proteasome. Our overall aim is to reveal the multiple regulatory levels that coordinate the 20S proteasome degradation route.
To achieve this goal we will carry out a comprehensive research program characterizing three distinct levels of 20S proteasome regulation:
Intra-molecular regulation- Revealing the intrinsic molecular switch that activates the latent 20S proteasome.
Inter-molecular regulation- Identifying novel proteins that bind the 20S proteasome to regulate its activity and characterizing their mechanism of function.
Cellular regulatory networks- Unraveling the cellular cues and multiple pathways that influence 20S proteasome activity using a novel systematic and unbiased screening approach.
Our experimental strategy involves the combination of biochemical approaches with native mass spectrometry, cross-linking and fluorescence measurements, complemented by cell biology analyses and high-throughput screening. Such a multidisciplinary approach, integrating in vitro and in vivo findings, will likely provide the much needed knowledge on the 20S proteasome degradation route. When completed, we anticipate that this work will be part of a new paradigm – no longer perceiving the 20S proteasome mediated degradation as a simple and passive event but rather a tightly regulated and coordinated process.
Max ERC Funding
1 500 000 €
Duration
Start date: 2015-04-01, End date: 2020-03-31
Project acronym 2SEXES_1GENOME
Project Sex-specific genetic effects on fitness and human disease
Researcher (PI) Edward Hugh Morrow
Host Institution (HI) THE UNIVERSITY OF SUSSEX
Country United Kingdom
Call Details Starting Grant (StG), LS8, ERC-2011-StG_20101109
Summary Darwin’s theory of natural selection rests on the principle that fitness variation in natural populations has a heritable component, on which selection acts, thereby leading to evolutionary change. A fundamental and so far unresolved question for the field of evolutionary biology is to identify the genetic loci responsible for this fitness variation, thereby coming closer to an understanding of how variation is maintained in the face of continual selection. One important complicating factor in the search for fitness related genes however is the existence of separate sexes – theoretical expectations and empirical data both suggest that sexually antagonistic genes are common. The phrase “two sexes, one genome” nicely sums up the problem; selection may favour alleles in one sex, even if they have detrimental effects on the fitness of the opposite sex, since it is their net effect across both sexes that determine the likelihood that alleles persist in a population. This theoretical framework raises an interesting, and so far entirely unexplored issue: that in one sex the functional performance of some alleles is predicted to be compromised and this effect may account for some common human diseases and conditions which show genotype-sex interactions. I propose to explore the genetic basis of sex-specific fitness in a model organism in both laboratory and natural conditions and to test whether those genes identified as having sexually antagonistic effects can help explain the incidence of human diseases that display sexual dimorphism in prevalence, age of onset or severity. This multidisciplinary project directly addresses some fundamental unresolved questions in evolutionary biology: the genetic basis and maintenance of fitness variation; the evolution of sexual dimorphism; and aims to provide novel insights into the genetic basis of some common human diseases.
Summary
Darwin’s theory of natural selection rests on the principle that fitness variation in natural populations has a heritable component, on which selection acts, thereby leading to evolutionary change. A fundamental and so far unresolved question for the field of evolutionary biology is to identify the genetic loci responsible for this fitness variation, thereby coming closer to an understanding of how variation is maintained in the face of continual selection. One important complicating factor in the search for fitness related genes however is the existence of separate sexes – theoretical expectations and empirical data both suggest that sexually antagonistic genes are common. The phrase “two sexes, one genome” nicely sums up the problem; selection may favour alleles in one sex, even if they have detrimental effects on the fitness of the opposite sex, since it is their net effect across both sexes that determine the likelihood that alleles persist in a population. This theoretical framework raises an interesting, and so far entirely unexplored issue: that in one sex the functional performance of some alleles is predicted to be compromised and this effect may account for some common human diseases and conditions which show genotype-sex interactions. I propose to explore the genetic basis of sex-specific fitness in a model organism in both laboratory and natural conditions and to test whether those genes identified as having sexually antagonistic effects can help explain the incidence of human diseases that display sexual dimorphism in prevalence, age of onset or severity. This multidisciplinary project directly addresses some fundamental unresolved questions in evolutionary biology: the genetic basis and maintenance of fitness variation; the evolution of sexual dimorphism; and aims to provide novel insights into the genetic basis of some common human diseases.
Max ERC Funding
1 500 000 €
Duration
Start date: 2012-01-01, End date: 2016-12-31
Project acronym 2STEPPARKIN
Project A novel two-step model for neurodegeneration in Parkinson’s disease
Researcher (PI) Emi Nagoshi
Host Institution (HI) UNIVERSITE DE GENEVE
Country Switzerland
Call Details Starting Grant (StG), LS5, ERC-2012-StG_20111109
Summary Parkinson’s disease (PD) is the second most common neurodegenerative disorder primarily caused by the progressive loss of dopaminergic (DA) neurons in the substantia nigra (SN). Despite the advances in gene discovery associated with PD, the knowledge of the PD pathogenesis is largely limited to the involvement of these genes in the generic cell death pathways, and why degeneration is specific to DA neurons and why the degeneration is progressive remain enigmatic. Broad goal of our work is therefore to elucidate the mechanisms underlying specific and progressive DA neuron degeneration in PD. Our new Drosophila model of PD ⎯Fer2 gene loss-of-function mutation⎯ is unusually well suited to address these questions. Fer2 mutants exhibit specific and progressive death of brain DA neurons as well as severe locomotor defects and short life span. Strikingly, the death of DA neuron is initiated in a small cluster of Fer2-expressing DA neurons and subsequently propagates to Fer2-negative DA neurons. We therefore propose a novel two-step model of the neurodegeneration in PD: primary cell death occurs in a specific subset of dopamindegic neurons that are genetically defined, and subsequently the failure of the neuronal connectivity triggers and propagates secondary cell death to remaining DA neurons. In this research, we will test this hypothesis and investigate the underlying molecular mechanisms. This will be the first study to examine circuit-dependency in DA neuron degeneration. Our approach will use a combination of non-biased genomic techniques and candidate-based screening, in addition to the powerful Drosophila genetic toolbox. Furthermore, to test this hypothesis beyond the Drosophila model, we will establish new mouse models of PD that exhibit progressive DA neuron degeneration. Outcome of this research will likely revolutionize the understanding of PD pathogenesis and open an avenue toward the discovery of effective therapy strategies against PD.
Summary
Parkinson’s disease (PD) is the second most common neurodegenerative disorder primarily caused by the progressive loss of dopaminergic (DA) neurons in the substantia nigra (SN). Despite the advances in gene discovery associated with PD, the knowledge of the PD pathogenesis is largely limited to the involvement of these genes in the generic cell death pathways, and why degeneration is specific to DA neurons and why the degeneration is progressive remain enigmatic. Broad goal of our work is therefore to elucidate the mechanisms underlying specific and progressive DA neuron degeneration in PD. Our new Drosophila model of PD ⎯Fer2 gene loss-of-function mutation⎯ is unusually well suited to address these questions. Fer2 mutants exhibit specific and progressive death of brain DA neurons as well as severe locomotor defects and short life span. Strikingly, the death of DA neuron is initiated in a small cluster of Fer2-expressing DA neurons and subsequently propagates to Fer2-negative DA neurons. We therefore propose a novel two-step model of the neurodegeneration in PD: primary cell death occurs in a specific subset of dopamindegic neurons that are genetically defined, and subsequently the failure of the neuronal connectivity triggers and propagates secondary cell death to remaining DA neurons. In this research, we will test this hypothesis and investigate the underlying molecular mechanisms. This will be the first study to examine circuit-dependency in DA neuron degeneration. Our approach will use a combination of non-biased genomic techniques and candidate-based screening, in addition to the powerful Drosophila genetic toolbox. Furthermore, to test this hypothesis beyond the Drosophila model, we will establish new mouse models of PD that exhibit progressive DA neuron degeneration. Outcome of this research will likely revolutionize the understanding of PD pathogenesis and open an avenue toward the discovery of effective therapy strategies against PD.
Max ERC Funding
1 518 960 €
Duration
Start date: 2013-06-01, End date: 2018-05-31
Project acronym 3CBIOTECH
Project Cold Carbon Catabolism of Microbial Communities underprinning a Sustainable Bioenergy and Biorefinery Economy
Researcher (PI) Gavin James Collins
Host Institution (HI) NATIONAL UNIVERSITY OF IRELAND GALWAY
Country Ireland
Call Details Starting Grant (StG), LS9, ERC-2010-StG_20091118
Summary The applicant will collaborate with Irish, European and U.S.-based colleagues to develop a sustainable biorefinery and bioenergy industry in Ireland and Europe. The focus of this ERC Starting Grant will be the application of classical microbiological, physiological and real-time polymerase chain reaction (PCR)-based assays, to qualitatively and quantitatively characterize microbial communities underpinning novel and innovative, low-temperature, anaerobic waste (and other biomass) conversion technologies, including municipal wastewater treatment and, demonstration- and full-scale biorefinery applications.
Anaerobic digestion (AD) is a naturally-occurring process, which is widely applied for the conversion of waste to methane-containing biogas. Low-temperature (<20 degrees C) AD has been applied by the applicant as a cost-effective alternative to mesophilic (c. 35C) AD for the treatment of several waste categories. However, the microbiology of low-temperature AD is poorly understood. The applicant will work with microbial consortia isolated from anaerobic bioreactors, which have been operated for long-term experiments (>3.5 years), and include organic acid-oxidizing, hydrogen-producing syntrophic microbes and hydrogen-consuming methanogens. A major focus of the project will be the ecophysiology of psychrotolerant and psychrophilic methanogens already identified and cultivated by the applicant. The project will also investigate the role(s) of poorly-understood Crenarchaeota populations and homoacetogenic bacteria, in complex consortia. The host organization is a leading player in the microbiology of waste-to-energy applications. The applicant will train a team of scientists in all aspects of the microbiology and bioengineering of biomass conversion systems.
Summary
The applicant will collaborate with Irish, European and U.S.-based colleagues to develop a sustainable biorefinery and bioenergy industry in Ireland and Europe. The focus of this ERC Starting Grant will be the application of classical microbiological, physiological and real-time polymerase chain reaction (PCR)-based assays, to qualitatively and quantitatively characterize microbial communities underpinning novel and innovative, low-temperature, anaerobic waste (and other biomass) conversion technologies, including municipal wastewater treatment and, demonstration- and full-scale biorefinery applications.
Anaerobic digestion (AD) is a naturally-occurring process, which is widely applied for the conversion of waste to methane-containing biogas. Low-temperature (<20 degrees C) AD has been applied by the applicant as a cost-effective alternative to mesophilic (c. 35C) AD for the treatment of several waste categories. However, the microbiology of low-temperature AD is poorly understood. The applicant will work with microbial consortia isolated from anaerobic bioreactors, which have been operated for long-term experiments (>3.5 years), and include organic acid-oxidizing, hydrogen-producing syntrophic microbes and hydrogen-consuming methanogens. A major focus of the project will be the ecophysiology of psychrotolerant and psychrophilic methanogens already identified and cultivated by the applicant. The project will also investigate the role(s) of poorly-understood Crenarchaeota populations and homoacetogenic bacteria, in complex consortia. The host organization is a leading player in the microbiology of waste-to-energy applications. The applicant will train a team of scientists in all aspects of the microbiology and bioengineering of biomass conversion systems.
Max ERC Funding
1 499 797 €
Duration
Start date: 2011-05-01, End date: 2016-04-30
Project acronym 3DBIOLUNG
Project Bioengineering lung tissue using extracellular matrix based 3D bioprinting
Researcher (PI) Darcy WAGNER
Host Institution (HI) LUNDS UNIVERSITET
Country Sweden
Call Details Starting Grant (StG), LS9, ERC-2018-STG
Summary Chronic lung diseases are increasing in prevalence with over 65 million patients worldwide. Lung transplantation remains the only potential option at end-stage disease. Around 4000 patients receive lung transplants annually with more awaiting transplantation, including 1000 patients in Europe. New options to increase available tissue for lung transplantation are desperately needed.
An exciting new research area focuses on generating lung tissue ex vivo using bioengineering approaches. Scaffolds can be generated from synthetic or biologically-derived (acellular) materials, seeded with cells and grown in a bioreactor prior to transplantation. Ideally, scaffolds would be seeded with cells derived from the transplant recipient, thus obviating the need for long-term immunosuppression. However, functional regeneration has yet to be achieved. New advances in 3D printing and 3D bioprinting (when cells are printed) indicate that this once thought of science-fiction concept might finally be mature enough for complex tissues, including lung. 3D bioprinting addresses a number of concerns identified in previous approaches, such as a) patient heterogeneity in acellular human scaffolds, b) anatomical differences in xenogeneic sources, c) lack of biological cues on synthetic materials and d) difficulty in manufacturing the complex lung architecture. 3D bioprinting could be a reproducible, scalable, and controllable approach for generating functional lung tissue.
The aim of this proposal is to use custom 3D bioprinters to generate constructs mimicking lung tissue using an innovative approach combining primary cells, the engineering reproducibility of synthetic materials, and the biologically conductive properties of acellular lung (hybrid). We will 3D bioprint hybrid murine and human lung tissue models and test gas exchange, angiogenesis and in vivo immune responses. This proposal will be a critical first step in demonstrating feasibility of 3D bioprinting lung tissue.
Summary
Chronic lung diseases are increasing in prevalence with over 65 million patients worldwide. Lung transplantation remains the only potential option at end-stage disease. Around 4000 patients receive lung transplants annually with more awaiting transplantation, including 1000 patients in Europe. New options to increase available tissue for lung transplantation are desperately needed.
An exciting new research area focuses on generating lung tissue ex vivo using bioengineering approaches. Scaffolds can be generated from synthetic or biologically-derived (acellular) materials, seeded with cells and grown in a bioreactor prior to transplantation. Ideally, scaffolds would be seeded with cells derived from the transplant recipient, thus obviating the need for long-term immunosuppression. However, functional regeneration has yet to be achieved. New advances in 3D printing and 3D bioprinting (when cells are printed) indicate that this once thought of science-fiction concept might finally be mature enough for complex tissues, including lung. 3D bioprinting addresses a number of concerns identified in previous approaches, such as a) patient heterogeneity in acellular human scaffolds, b) anatomical differences in xenogeneic sources, c) lack of biological cues on synthetic materials and d) difficulty in manufacturing the complex lung architecture. 3D bioprinting could be a reproducible, scalable, and controllable approach for generating functional lung tissue.
The aim of this proposal is to use custom 3D bioprinters to generate constructs mimicking lung tissue using an innovative approach combining primary cells, the engineering reproducibility of synthetic materials, and the biologically conductive properties of acellular lung (hybrid). We will 3D bioprint hybrid murine and human lung tissue models and test gas exchange, angiogenesis and in vivo immune responses. This proposal will be a critical first step in demonstrating feasibility of 3D bioprinting lung tissue.
Max ERC Funding
1 499 975 €
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 3DPROTEINPUZZLES
Project Shape-directed protein assembly design
Researcher (PI) Lars Ingemar ANDRe
Host Institution (HI) MAX IV Laboratory, Lund University
Country Sweden
Call Details Consolidator Grant (CoG), LS9, ERC-2017-COG
Summary Large protein complexes carry out some of the most complex functions in biology. Such structures are often assembled spontaneously from individual components through the process of self-assembly. If self-assembled protein complexes could be engineered from first principle it would enable a wide range of applications in biomedicine, nanotechnology and materials science. Recently, approaches to rationally design proteins to self-assembly into predefined structures have emerged. The highlight of this work is the design of protein cages that may be engineered into protein containers. However, current approaches for self-assembly design does not result in the assemblies with the required structural complexity to encode many of the sophisticated functions found in nature. To move forward, we have to learn how to engineer protein subunits with more than one designed interface that can assemble into tightly interacting complexes. In this proposal we propose a new protein design paradigm, shape directed protein design, in order to address shortcomings of the current methodology. The proposed method combines geometric shape matching and computational protein design. Using this approach we will de novo design assemblies with a wide variety of structural states, including protein complexes with cyclic and dihedral symmetry as well as icosahedral protein capsids built from novel protein building blocks. To enable these two design challenges we also develop a high-throughput assay to measure assembly stability in vivo that builds on a three-color fluorescent assay. This method will not only facilitate the screening of orders of magnitude more design constructs, but also enable the application of directed evolution to experimentally improve stable and assembly properties of designed containers as well as other designed assemblies.
Summary
Large protein complexes carry out some of the most complex functions in biology. Such structures are often assembled spontaneously from individual components through the process of self-assembly. If self-assembled protein complexes could be engineered from first principle it would enable a wide range of applications in biomedicine, nanotechnology and materials science. Recently, approaches to rationally design proteins to self-assembly into predefined structures have emerged. The highlight of this work is the design of protein cages that may be engineered into protein containers. However, current approaches for self-assembly design does not result in the assemblies with the required structural complexity to encode many of the sophisticated functions found in nature. To move forward, we have to learn how to engineer protein subunits with more than one designed interface that can assemble into tightly interacting complexes. In this proposal we propose a new protein design paradigm, shape directed protein design, in order to address shortcomings of the current methodology. The proposed method combines geometric shape matching and computational protein design. Using this approach we will de novo design assemblies with a wide variety of structural states, including protein complexes with cyclic and dihedral symmetry as well as icosahedral protein capsids built from novel protein building blocks. To enable these two design challenges we also develop a high-throughput assay to measure assembly stability in vivo that builds on a three-color fluorescent assay. This method will not only facilitate the screening of orders of magnitude more design constructs, but also enable the application of directed evolution to experimentally improve stable and assembly properties of designed containers as well as other designed assemblies.
Max ERC Funding
2 325 292 €
Duration
Start date: 2018-06-01, End date: 2023-05-31
Project acronym 3S-BTMUC
Project Soft, Slimy, Sliding Interfaces: Biotribological Properties of Mucins and Mucus gels
Researcher (PI) Seunghwan Lee
Host Institution (HI) DANMARKS TEKNISKE UNIVERSITET
Country Denmark
Call Details Starting Grant (StG), LS9, ERC-2010-StG_20091118
Summary Mucins are a family of high-molecular-weight glycoproteins and a major macromolecular constituent in slimy mucus gels that are covering the surface of internal biological tissues. A primary role of mucus gels in biological systems is known to be the protection and lubrication of underlying epithelial cell surfaces. This is intuitively well appreciated by both science community and the public, and yet detailed lubrication properties of mucins and mucus gels have remained largely unexplored to date. Detailed and systematic understanding of the lubrication mechanism of mucus gels is significant from many angles; firstly, lubricity of mucus gels is closely related with fundamental functions of various human organs, such as eye blinking, mastication in oral cavity, swallowing through esophagus, digestion in stomach, breathing through air way and respiratory organs, and thus often indicates the health state of those organs. Furthermore, for the application of various tissue-contacting devices or personal care products, e.g. catheters, endoscopes, and contact lenses, mucus gel layer is the first counter surface that comes into the mechanical and tribological contacts with them. Finally, remarkable lubricating performance by mucins and mucus gels in biological systems may provide many useful and possibly innovative hints in utilizing water as base lubricant for man-made engineering systems. This project thus proposes to carry out a 5 year research program focusing on exploring the lubricity of mucins and mucus gels by combining a broad range of experimental approaches in biology and tribology.
Summary
Mucins are a family of high-molecular-weight glycoproteins and a major macromolecular constituent in slimy mucus gels that are covering the surface of internal biological tissues. A primary role of mucus gels in biological systems is known to be the protection and lubrication of underlying epithelial cell surfaces. This is intuitively well appreciated by both science community and the public, and yet detailed lubrication properties of mucins and mucus gels have remained largely unexplored to date. Detailed and systematic understanding of the lubrication mechanism of mucus gels is significant from many angles; firstly, lubricity of mucus gels is closely related with fundamental functions of various human organs, such as eye blinking, mastication in oral cavity, swallowing through esophagus, digestion in stomach, breathing through air way and respiratory organs, and thus often indicates the health state of those organs. Furthermore, for the application of various tissue-contacting devices or personal care products, e.g. catheters, endoscopes, and contact lenses, mucus gel layer is the first counter surface that comes into the mechanical and tribological contacts with them. Finally, remarkable lubricating performance by mucins and mucus gels in biological systems may provide many useful and possibly innovative hints in utilizing water as base lubricant for man-made engineering systems. This project thus proposes to carry out a 5 year research program focusing on exploring the lubricity of mucins and mucus gels by combining a broad range of experimental approaches in biology and tribology.
Max ERC Funding
1 432 920 €
Duration
Start date: 2011-04-01, End date: 2016-03-31
Project acronym 5HT-OPTOGENETICS
Project Optogenetic Analysis of Serotonin Function in the Mammalian Brain
Researcher (PI) Zachary Mainen
Host Institution (HI) FUNDACAO D. ANNA SOMMER CHAMPALIMAUD E DR. CARLOS MONTEZ CHAMPALIMAUD
Country Portugal
Call Details Advanced Grant (AdG), LS5, ERC-2009-AdG
Summary Serotonin (5-HT) is implicated in a wide spectrum of brain functions and disorders. However, its functions remain controversial and enigmatic. We suggest that past work on the 5-HT system have been significantly hampered by technical limitations in the selectivity and temporal resolution of the conventional pharmacological and electrophysiological methods that have been applied. We therefore propose to apply novel optogenetic methods that will allow us to overcome these limitations and thereby gain new insight into the biological functions of this important molecule. In preliminary studies, we have demonstrated that we can deliver exogenous proteins specifically to 5-HT neurons using viral vectors. Our objectives are to (1) record, (2) stimulate and (3) silence the activity of 5-HT neurons with high molecular selectivity and temporal precision by using genetically-encoded sensors, activators and inhibitors of neural function. These tools will allow us to monitor and control the 5-HT system in real-time in freely-behaving animals and thereby to establish causal links between information processing in 5-HT neurons and specific behaviors. In combination with quantitative behavioral assays, we will use this approach to define the role of 5-HT in sensory, motor and cognitive functions. The significance of the work is three-fold. First, we will establish a new arsenal of tools for probing the physiological and behavioral functions of 5-HT neurons. Second, we will make definitive tests of major hypotheses of 5-HT function. Third, we will have possible therapeutic applications. In this way, the proposed work has the potential for a major impact in research on the role of 5-HT in brain function and dysfunction.
Summary
Serotonin (5-HT) is implicated in a wide spectrum of brain functions and disorders. However, its functions remain controversial and enigmatic. We suggest that past work on the 5-HT system have been significantly hampered by technical limitations in the selectivity and temporal resolution of the conventional pharmacological and electrophysiological methods that have been applied. We therefore propose to apply novel optogenetic methods that will allow us to overcome these limitations and thereby gain new insight into the biological functions of this important molecule. In preliminary studies, we have demonstrated that we can deliver exogenous proteins specifically to 5-HT neurons using viral vectors. Our objectives are to (1) record, (2) stimulate and (3) silence the activity of 5-HT neurons with high molecular selectivity and temporal precision by using genetically-encoded sensors, activators and inhibitors of neural function. These tools will allow us to monitor and control the 5-HT system in real-time in freely-behaving animals and thereby to establish causal links between information processing in 5-HT neurons and specific behaviors. In combination with quantitative behavioral assays, we will use this approach to define the role of 5-HT in sensory, motor and cognitive functions. The significance of the work is three-fold. First, we will establish a new arsenal of tools for probing the physiological and behavioral functions of 5-HT neurons. Second, we will make definitive tests of major hypotheses of 5-HT function. Third, we will have possible therapeutic applications. In this way, the proposed work has the potential for a major impact in research on the role of 5-HT in brain function and dysfunction.
Max ERC Funding
2 318 636 €
Duration
Start date: 2010-07-01, End date: 2015-12-31
Project acronym 5HTCircuits
Project Modulation of cortical circuits and predictive neural coding by serotonin
Researcher (PI) Zachary Mainen
Host Institution (HI) FUNDACAO D. ANNA SOMMER CHAMPALIMAUD E DR. CARLOS MONTEZ CHAMPALIMAUD
Country Portugal
Call Details Advanced Grant (AdG), LS5, ERC-2014-ADG
Summary Serotonin (5-HT) is a central neuromodulator and a major target of therapeutic psychoactive drugs, but relatively little is known about how it modulates information processing in neural circuits. The theory of predictive coding postulates that the brain combines raw bottom-up sensory information with top-down information from internal models to make perceptual inferences about the world. We hypothesize, based on preliminary data and prior literature, that a role of 5-HT in this process is to report prediction errors and promote the suppression and weakening of erroneous internal models. We propose that it does this by inhibiting top-down relative to bottom-up cortical information flow. To test this hypothesis, we propose a set of experiments in mice performing olfactory perceptual tasks. Our specific aims are: (1) We will test whether 5-HT neurons encode sensory prediction errors. (2) We will test their causal role in using predictive cues to guide perceptual decisions. (3) We will characterize how 5-HT influences the encoding of sensory information by neuronal populations in the olfactory cortex and identify the underlying circuitry. (4) Finally, we will map the effects of 5-HT across the whole brain and use this information to target further causal manipulations to specific 5-HT projections. We accomplish these aims using state-of-the-art optogenetic, electrophysiological and imaging techniques (including 9.4T small-animal functional magnetic resonance imaging) as well as psychophysical tasks amenable to quantitative analysis and computational theory. Together, these experiments will tackle multiple facets of an important general computational question, bringing to bear an array of cutting-edge technologies to address with unprecedented mechanistic detail how 5-HT impacts neural coding and perceptual decision-making.
Summary
Serotonin (5-HT) is a central neuromodulator and a major target of therapeutic psychoactive drugs, but relatively little is known about how it modulates information processing in neural circuits. The theory of predictive coding postulates that the brain combines raw bottom-up sensory information with top-down information from internal models to make perceptual inferences about the world. We hypothesize, based on preliminary data and prior literature, that a role of 5-HT in this process is to report prediction errors and promote the suppression and weakening of erroneous internal models. We propose that it does this by inhibiting top-down relative to bottom-up cortical information flow. To test this hypothesis, we propose a set of experiments in mice performing olfactory perceptual tasks. Our specific aims are: (1) We will test whether 5-HT neurons encode sensory prediction errors. (2) We will test their causal role in using predictive cues to guide perceptual decisions. (3) We will characterize how 5-HT influences the encoding of sensory information by neuronal populations in the olfactory cortex and identify the underlying circuitry. (4) Finally, we will map the effects of 5-HT across the whole brain and use this information to target further causal manipulations to specific 5-HT projections. We accomplish these aims using state-of-the-art optogenetic, electrophysiological and imaging techniques (including 9.4T small-animal functional magnetic resonance imaging) as well as psychophysical tasks amenable to quantitative analysis and computational theory. Together, these experiments will tackle multiple facets of an important general computational question, bringing to bear an array of cutting-edge technologies to address with unprecedented mechanistic detail how 5-HT impacts neural coding and perceptual decision-making.
Max ERC Funding
2 486 074 €
Duration
Start date: 2016-01-01, End date: 2020-12-31
