Project acronym AN07AT
Project Understanding computational roles of new neurons generated in the adult hippocampus
Researcher (PI) Ayumu Tashiro
Host Institution (HI) NORGES TEKNISK-NATURVITENSKAPELIGE UNIVERSITET NTNU
Call Details Starting Grant (StG), LS4, ERC-2007-StG
Summary New neurons are continuously generated in certain regions of adult mammalian brain. One of those regions is the dentate gyrus, a subregion of hippocampus, which is essential for memory formation. Although these new neurons in the adult dentate gyrus are thought to have an important role in learning and memory, it is largely unclear how new neurons are involved in information processing and storage underlying memory. Because new neurons constitute a minor portion of intermingled local neuronal population, simple application of conventional techniques such as multi-unit extracellular recording and pharmacological lesion are not suitable for the functional analysis of new neurons. In this proposed research program, I will combine multi-unit recording and behavioral analysis with virus mediated, cell-type-specific genetic manipulation of neuronal activity, to investigate computational roles of new neurons in learning and memory. Specifically, I will determine: 1) specific memory processes that require new neurons, 2) dynamic patterns of activity that new neurons express during memory-related behavior, 3) influence of new neurons on their downstream structure. Further, based on the information obtained by these three lines of studies, we will establish causal relationship between specific memory-related behavior and specific pattern of activity in new neurons. Solving these issues will cooperatively provide important insight into the understanding of computational roles performed by adult neurogenesis. The information on the function of new neurons in normal brain could contribute to future development of efficient therapeutic strategy for a variety of brain disorders.
Summary
New neurons are continuously generated in certain regions of adult mammalian brain. One of those regions is the dentate gyrus, a subregion of hippocampus, which is essential for memory formation. Although these new neurons in the adult dentate gyrus are thought to have an important role in learning and memory, it is largely unclear how new neurons are involved in information processing and storage underlying memory. Because new neurons constitute a minor portion of intermingled local neuronal population, simple application of conventional techniques such as multi-unit extracellular recording and pharmacological lesion are not suitable for the functional analysis of new neurons. In this proposed research program, I will combine multi-unit recording and behavioral analysis with virus mediated, cell-type-specific genetic manipulation of neuronal activity, to investigate computational roles of new neurons in learning and memory. Specifically, I will determine: 1) specific memory processes that require new neurons, 2) dynamic patterns of activity that new neurons express during memory-related behavior, 3) influence of new neurons on their downstream structure. Further, based on the information obtained by these three lines of studies, we will establish causal relationship between specific memory-related behavior and specific pattern of activity in new neurons. Solving these issues will cooperatively provide important insight into the understanding of computational roles performed by adult neurogenesis. The information on the function of new neurons in normal brain could contribute to future development of efficient therapeutic strategy for a variety of brain disorders.
Max ERC Funding
1 991 743 €
Duration
Start date: 2009-01-01, End date: 2013-12-31
Project acronym BODY-OWNERSHIP
Project Neural mechanisms of body ownership and the projection of ownership onto artificial bodies
Researcher (PI) H. Henrik Ehrsson
Host Institution (HI) KAROLINSKA INSTITUTET
Call Details Starting Grant (StG), LS4, ERC-2007-StG
Summary How do we recognize that our limbs are part of our own body, and why do we feel that one’s self is located inside the body? These fundamental questions have been discussed in theology, philosophy and psychology for millennia. The aim of my ground-breaking research programme is to identify the neuronal mechanisms that produce the sense of ownership of the body, and the processes responsible for the feeling that the self is located inside the physical body. To solve these questions I will adopt an inter-disciplinary approach using state-of-the-art methods from the fields of imaging neuroscience, experimental psychology, computer science and robotics. My first hypothesis is that the mechanism for body ownership is the integration of information from different sensory modalities (vision, touch and muscle sense) in multi-sensory brain areas (ventral premotor and intraparietal cortex). My second hypothesis is that the sense of where you are located in the environment is mediated by allocentric spatial representations in medial temporal lobes. To test this, I will use perceptual illusions and virtual-reality techniques that allow me to manipulate body ownership and the perceived location of the self, in conjunction with non-invasive recordings of brain activity in healthy humans. Functional magnetic resonance imaging and electroencephalography will be used to identify the neuronal correlates of ownership and ‘in-body experiences’, while transcranial magnetic stimulation will be used to examine the causal relationship between neural activity and ownership. It is no overstatement to say that my pioneering work could define a new sub-field in cognitive neuroscience dealing with how the brain represents the self. These basic scientific discoveries will be used in new frontier applications. For example, the development of a prosthetic limb that feels just like a real limb, and a method of controlling humanoid robots by the illusion of ‘becoming the robot’.
Summary
How do we recognize that our limbs are part of our own body, and why do we feel that one’s self is located inside the body? These fundamental questions have been discussed in theology, philosophy and psychology for millennia. The aim of my ground-breaking research programme is to identify the neuronal mechanisms that produce the sense of ownership of the body, and the processes responsible for the feeling that the self is located inside the physical body. To solve these questions I will adopt an inter-disciplinary approach using state-of-the-art methods from the fields of imaging neuroscience, experimental psychology, computer science and robotics. My first hypothesis is that the mechanism for body ownership is the integration of information from different sensory modalities (vision, touch and muscle sense) in multi-sensory brain areas (ventral premotor and intraparietal cortex). My second hypothesis is that the sense of where you are located in the environment is mediated by allocentric spatial representations in medial temporal lobes. To test this, I will use perceptual illusions and virtual-reality techniques that allow me to manipulate body ownership and the perceived location of the self, in conjunction with non-invasive recordings of brain activity in healthy humans. Functional magnetic resonance imaging and electroencephalography will be used to identify the neuronal correlates of ownership and ‘in-body experiences’, while transcranial magnetic stimulation will be used to examine the causal relationship between neural activity and ownership. It is no overstatement to say that my pioneering work could define a new sub-field in cognitive neuroscience dealing with how the brain represents the self. These basic scientific discoveries will be used in new frontier applications. For example, the development of a prosthetic limb that feels just like a real limb, and a method of controlling humanoid robots by the illusion of ‘becoming the robot’.
Max ERC Funding
909 850 €
Duration
Start date: 2008-12-01, End date: 2013-11-30
Project acronym BRAINPLASTICITY
Project In vivo imaging of functional plasticity in the mammalian brain
Researcher (PI) Adi Mizrahi
Host Institution (HI) THE HEBREW UNIVERSITY OF JERUSALEM
Call Details Starting Grant (StG), LS4, ERC-2007-StG
Summary "The dynamic nature of the brain operates at disparate time scales ranging from milliseconds to months. How do single neurons change over such long time scales? This question remains stubborn to answer in the field of brain plasticity mainly because of limited tools to study the physiology of single neurons over time in the complex environment of the brain. The research aim of this proposal is to reveal the physiological changes of single neurons in the mammalian brain over disparate time scales using time-lapse optical imaging. Specifically, we aim to establish a new team that will develop genetic and optical tools to probe the physiological activity of single neurons, in vivo. As a model system, we will study a unique neuronal population in the mammalian brain; the adult-born local neurons in the olfactory bulb. These neurons have tremendous potential to reveal how neurons develop and maintain in the intact brain because they are accessible both genetically and optically. By following the behavior of adult-born neurons in vivo we will discover how neurons mature and maintain over days and weeks. If our objectives will be met, this study has the potential to significantly ""raise the bar"" on how neuronal plasticity is studied and reveal some basic secrets of the ever changing mammalian brain."
Summary
"The dynamic nature of the brain operates at disparate time scales ranging from milliseconds to months. How do single neurons change over such long time scales? This question remains stubborn to answer in the field of brain plasticity mainly because of limited tools to study the physiology of single neurons over time in the complex environment of the brain. The research aim of this proposal is to reveal the physiological changes of single neurons in the mammalian brain over disparate time scales using time-lapse optical imaging. Specifically, we aim to establish a new team that will develop genetic and optical tools to probe the physiological activity of single neurons, in vivo. As a model system, we will study a unique neuronal population in the mammalian brain; the adult-born local neurons in the olfactory bulb. These neurons have tremendous potential to reveal how neurons develop and maintain in the intact brain because they are accessible both genetically and optically. By following the behavior of adult-born neurons in vivo we will discover how neurons mature and maintain over days and weeks. If our objectives will be met, this study has the potential to significantly ""raise the bar"" on how neuronal plasticity is studied and reveal some basic secrets of the ever changing mammalian brain."
Max ERC Funding
1 750 000 €
Duration
Start date: 2008-08-01, End date: 2013-07-31
Project acronym CODING_IN_V1
Project How visual information is represented by neuronal networks in the primary visual cortex
Researcher (PI) Thomas D. Mrsic-Flogel
Host Institution (HI) UNIVERSITY COLLEGE LONDON
Call Details Starting Grant (StG), LS4, ERC-2007-StG
Summary The vast majority of our knowledge about how the brain encodes information has been obtained from recordings of one or few neurons at a time or from global mapping methods such as fMRI. These approaches have left unexplored how neuronal activity is distributed in space and time within a cortical column and how hundreds of neurons interact to process sensory information. By taking advantage of the most recent advances in two-photon microscopy, the proposed project addresses two broad aims, with a particular focus on the function and development of primary visual cortex: 1) to understand how cortical neuronal networks encode visual information, and 2) to understand how they become specialised for sensory processing during postnatal development. For the first aim, we will use in vivo two-photon calcium imaging to record activity simultaneously from hundreds of neurons in visual cortex while showing different visual stimuli to anaesthetised mice. This approach enables us for the first time to characterise in detail how individual neurons and neuronal subsets interact within a large cortical network in response to artificial and natural stimuli. Genetically-encoded fluorescent proteins expressed in distinct cell-types will inform us how excitatory and inhibitory neurons interact to shape population responses during vision. For the second aim, the same approach will be used to describe the maturation of cortical network function after the onset of vision and to assess the role of visual experience in this process. We will additionally use Channelrhodopsin-2, a genetic tool for remote control of action potential firing, to examine the role of correlated neuronal activity on establishment of functional cortical circuits. Together, this work will bring us closer to unravelling how sensory coding emerges on the level of neuronal networks.
Summary
The vast majority of our knowledge about how the brain encodes information has been obtained from recordings of one or few neurons at a time or from global mapping methods such as fMRI. These approaches have left unexplored how neuronal activity is distributed in space and time within a cortical column and how hundreds of neurons interact to process sensory information. By taking advantage of the most recent advances in two-photon microscopy, the proposed project addresses two broad aims, with a particular focus on the function and development of primary visual cortex: 1) to understand how cortical neuronal networks encode visual information, and 2) to understand how they become specialised for sensory processing during postnatal development. For the first aim, we will use in vivo two-photon calcium imaging to record activity simultaneously from hundreds of neurons in visual cortex while showing different visual stimuli to anaesthetised mice. This approach enables us for the first time to characterise in detail how individual neurons and neuronal subsets interact within a large cortical network in response to artificial and natural stimuli. Genetically-encoded fluorescent proteins expressed in distinct cell-types will inform us how excitatory and inhibitory neurons interact to shape population responses during vision. For the second aim, the same approach will be used to describe the maturation of cortical network function after the onset of vision and to assess the role of visual experience in this process. We will additionally use Channelrhodopsin-2, a genetic tool for remote control of action potential firing, to examine the role of correlated neuronal activity on establishment of functional cortical circuits. Together, this work will bring us closer to unravelling how sensory coding emerges on the level of neuronal networks.
Max ERC Funding
1 080 000 €
Duration
Start date: 2008-07-01, End date: 2013-06-30
Project acronym CORTEXSELFCONTROL
Project Self-Modulating Neurons in the Cerebral Cortex: From Molecular Mechanisms to Cortical Network Activities
Researcher (PI) Alberto Bacci
Host Institution (HI) INSTITUT DU CERVEAU ET DE LA MOELLE EPINIERE
Call Details Starting Grant (StG), LS4, ERC-2007-StG
Summary In the mammalian brain, the neocortex is the site where sensory information is integrated into complex cognitive functions. This is accomplished by the activity of both principal glutamatergic neurons and locally-projecting inhibitory GABAergic interneurons, interconnected in complex networks. Inhibitory neurons play several key roles in neocortical function. For example, they shape sensory receptive fields and drive several high frequency network oscillations. On the other hand, defects in their function can lead to devastating diseases, such as epilepsy and schizophrenia. Cortical interneurons represent a highly heterogeneous cell population. Understanding the specific role of each interneuron subtype within cortical microcircuits is still a crucial open question. We have examined properties of two major functional interneuron subclasses in neocortical layer V: fast-spiking (FS) and low-threshold spiking (LTS) cells. Our previous data indicate that each group expresses a novel form of self inhibition, namely autaptic inhibitory transmission in FS cells and an endocannabinoid-mediated slow self inhibition in LTS interneurons. In this proposal we will address three major questions relevant to self-inhibition of neocortical interneurons: 1) What is the role of FS cell autapses in coordinating fast network synchrony? 2) What are the molecular mechanisms underlying autaptic asynchronous release, prolonging FS cell self-inhibition by several seconds, and what is its relevance during physiological and pathological network activities? 3) What are the induction mechanisms, the molecular players involved and the functional roles within cortical microcircuits of the endocannabinoid-mediated long-lasting self-inhibition in LTS interneurons? Results of these experiments will lead to a better understanding of GABAergic interneuron regulation of neocortical excitability, relevant to both normal and pathological cortical function.
Summary
In the mammalian brain, the neocortex is the site where sensory information is integrated into complex cognitive functions. This is accomplished by the activity of both principal glutamatergic neurons and locally-projecting inhibitory GABAergic interneurons, interconnected in complex networks. Inhibitory neurons play several key roles in neocortical function. For example, they shape sensory receptive fields and drive several high frequency network oscillations. On the other hand, defects in their function can lead to devastating diseases, such as epilepsy and schizophrenia. Cortical interneurons represent a highly heterogeneous cell population. Understanding the specific role of each interneuron subtype within cortical microcircuits is still a crucial open question. We have examined properties of two major functional interneuron subclasses in neocortical layer V: fast-spiking (FS) and low-threshold spiking (LTS) cells. Our previous data indicate that each group expresses a novel form of self inhibition, namely autaptic inhibitory transmission in FS cells and an endocannabinoid-mediated slow self inhibition in LTS interneurons. In this proposal we will address three major questions relevant to self-inhibition of neocortical interneurons: 1) What is the role of FS cell autapses in coordinating fast network synchrony? 2) What are the molecular mechanisms underlying autaptic asynchronous release, prolonging FS cell self-inhibition by several seconds, and what is its relevance during physiological and pathological network activities? 3) What are the induction mechanisms, the molecular players involved and the functional roles within cortical microcircuits of the endocannabinoid-mediated long-lasting self-inhibition in LTS interneurons? Results of these experiments will lead to a better understanding of GABAergic interneuron regulation of neocortical excitability, relevant to both normal and pathological cortical function.
Max ERC Funding
996 000 €
Duration
Start date: 2008-10-01, End date: 2014-03-31
Project acronym EMPATHICBRAIN
Project Plasticity of the Empathic Brain: Structural and Functional MRI Studies on the Effect of Empathy Training on the Human Brain and Prosocial Behaviour
Researcher (PI) Tania Singer
Host Institution (HI) MAX-PLANCK-GESELLSCHAFT ZUR FORDERUNG DER WISSENSCHAFTEN EV
Call Details Starting Grant (StG), LS4, ERC-2007-StG
Summary Social neuroscientists study the neural mechanisms underlying our capacity to understand our own and other people’s feelings. Despite neuroscientists’ advances in plasticity research and empathy research, little is known about cortical and behavioural plasticity in emotion understanding and empathy. Clearly, in today’s world, acquiring the capacity to effectively enhance empathy and prosocial behaviour is of the utmost importance. In the present project, we will investigate the malleability of empathy via training. We will adopt a multimethod and interdisciplinary approach, combining techniques and paradigms from the fields of neuroscience, (bio-)psychology, and economics. Studies 1-3 will provide a cross-sectional look at structural and functional differences in the brains of individuals scoring high vs. low on empathy, of those with pathological deficits in empathy (psychopaths, alexithymics), and of individuals starting vs. finishing a three-year training program in Carl Rogers’ person-centred therapy, which aims to increase emotional capacity and empathy. Study 4 will examine brain plasticity using real-time fMRI: Participants will learn to self-regulate brain activity through the use of immediate feedback from emotion-related brain areas while practicing certain mental techniques. In Study 5, a small-scale longitudinal study, healthy individuals will receive extensive training by professional instructors in either empathy- or memory-enhancing techniques previously developed in the East and the West. We will measure training-related changes in brain structure and functioning, in hormone levels, and in behaviour. Evidence for emotional brain plasticity in adults and children would not only have important implications for the implementation of scientifically validated, effective training programs for schools and for economic and political organizations, but also for the treatment of the marked social deficits in autistic and psychopathic populations.
Summary
Social neuroscientists study the neural mechanisms underlying our capacity to understand our own and other people’s feelings. Despite neuroscientists’ advances in plasticity research and empathy research, little is known about cortical and behavioural plasticity in emotion understanding and empathy. Clearly, in today’s world, acquiring the capacity to effectively enhance empathy and prosocial behaviour is of the utmost importance. In the present project, we will investigate the malleability of empathy via training. We will adopt a multimethod and interdisciplinary approach, combining techniques and paradigms from the fields of neuroscience, (bio-)psychology, and economics. Studies 1-3 will provide a cross-sectional look at structural and functional differences in the brains of individuals scoring high vs. low on empathy, of those with pathological deficits in empathy (psychopaths, alexithymics), and of individuals starting vs. finishing a three-year training program in Carl Rogers’ person-centred therapy, which aims to increase emotional capacity and empathy. Study 4 will examine brain plasticity using real-time fMRI: Participants will learn to self-regulate brain activity through the use of immediate feedback from emotion-related brain areas while practicing certain mental techniques. In Study 5, a small-scale longitudinal study, healthy individuals will receive extensive training by professional instructors in either empathy- or memory-enhancing techniques previously developed in the East and the West. We will measure training-related changes in brain structure and functioning, in hormone levels, and in behaviour. Evidence for emotional brain plasticity in adults and children would not only have important implications for the implementation of scientifically validated, effective training programs for schools and for economic and political organizations, but also for the treatment of the marked social deficits in autistic and psychopathic populations.
Max ERC Funding
1 499 821 €
Duration
Start date: 2008-09-01, End date: 2014-08-31
Project acronym INSTINCTIVE DRIVES
Project Orchestration of instinctive drives
Researcher (PI) Denis Burdakov
Host Institution (HI) MEDICAL RESEARCH COUNCIL
Call Details Starting Grant (StG), LS4, ERC-2007-StG
Summary A major goal of 21st century science is to protect human health from the growing mismatch between ancient behavioural instincts and modern socio-economic reality. This is especially vital for basic instinctive drives such as appetite, which lead to overeating when food is readily available. The resulting obesity is responsible for 100,000s of premature deaths per year in Europe and North America, and this number is rapidly rising. Sleep is another powerful instinct which substantially contributes to premature human death, for example from car accidents caused by tiredness. Thus “self-destructive” behaviours caused by inappropriate activation of feeding and sleep drives take a devastating social and economic toll in developed countries, and there is a huge unmet need for effective therapies in this area. To design these therapies, we need to understand the brain mechanisms of instinctive drives. However, brain circuits regulating appetite and sleep have only been delineated in the past few years, and their principles of operation are poorly understood at present. The broad aim of my newly-established laboratory is to fill this gap in knowledge. To understand neural signals controlling instinctive drives, and their relationship to well-being and disease, the following questions must be answered: 1) how do neurons that control appetite and sleep generate their electrical and chemical signals? ) how do these neurons interact with each other? 3) how are these neurons altered in disorders of energy balance and sleep? Our objective for the next five years is to address these key unknowns by focusing on neurons known to be unequivocally important for normal sleep and appetite, the orexin and MCH neurons of the lateral hypothalamus.
Summary
A major goal of 21st century science is to protect human health from the growing mismatch between ancient behavioural instincts and modern socio-economic reality. This is especially vital for basic instinctive drives such as appetite, which lead to overeating when food is readily available. The resulting obesity is responsible for 100,000s of premature deaths per year in Europe and North America, and this number is rapidly rising. Sleep is another powerful instinct which substantially contributes to premature human death, for example from car accidents caused by tiredness. Thus “self-destructive” behaviours caused by inappropriate activation of feeding and sleep drives take a devastating social and economic toll in developed countries, and there is a huge unmet need for effective therapies in this area. To design these therapies, we need to understand the brain mechanisms of instinctive drives. However, brain circuits regulating appetite and sleep have only been delineated in the past few years, and their principles of operation are poorly understood at present. The broad aim of my newly-established laboratory is to fill this gap in knowledge. To understand neural signals controlling instinctive drives, and their relationship to well-being and disease, the following questions must be answered: 1) how do neurons that control appetite and sleep generate their electrical and chemical signals? ) how do these neurons interact with each other? 3) how are these neurons altered in disorders of energy balance and sleep? Our objective for the next five years is to address these key unknowns by focusing on neurons known to be unequivocally important for normal sleep and appetite, the orexin and MCH neurons of the lateral hypothalamus.
Max ERC Funding
1 299 999 €
Duration
Start date: 2008-10-01, End date: 2013-09-30
Project acronym ISCATAXIA
Project Unraveling the molecular mechanisms leading to cellular dysfunction in diseases linked to defects in mitochondrial iron-sulfur cluster metabolism
Researcher (PI) Hélène Monique Sadoulet Puccio
Host Institution (HI) CENTRE EUROPEEN DE RECHERCHE EN BIOLOGIE ET MEDECINE
Call Details Starting Grant (StG), LS4, ERC-2007-StG
Summary The project aims at unraveling the molecular pathophysiology of recessive ataxias, a heterogeneous set of severely disabling neurodegenerative disorders due to loss of function of proteins involved either in mitochondrial/metabolic pathways or DNA repair. Friedreich ataxia, the most common form, is due to partial loss of function of frataxin, a mitochondrial protein involved in iron-sulfur cluster (ISC) biogenesis. Furthermore, the rare X-linked sideroblastic anemia with cerebellar ataxia is caused by mutation in ABCb7, an ATP-binding cassette transporter of the mitochondrial inner membrane necessary for cytosolic ISC export. ISC are versatile co-factors of proteins involved in electron transport, enzyme catalysis and regulation of gene expression. The synthesis and insertion of ISC into apoproteins involve complex machineries that are still poorly understood in the mammalian cell. The objectives of this proposal are: 1) to elucidate ISC biogenesis and metabolism in the mammalian cell, with an emphasis on the role of frataxin and ABCb7; 2) to better understand the molecular pathways that are involved in neuronal dysfunction due to defects in mitochondrial ISC metabolism. These objectives will be accomplished by a multidisciplinary approach combining molecular and biochemical approaches to study the ISC assembly machineries, bioinformatic and proteomic studies to identify new Fe-S proteins, the development and pathological analysis of animal and cellular models to dissect the molecular mechanisms, and transcriptomic analysis to uncover the common pathways among recessive ataxias. A specific focus of the proposal will be the involvement of DNA damage response pathways in neuronal dysfunction, as several DNA repair enzymes have recently been identified as Fe-S proteins and thus might be directly affected by frataxin and ABCb7 deficiency. This proposal should lead to the identification of different pathways for therapeutic intervention for these devastating disorders.
Summary
The project aims at unraveling the molecular pathophysiology of recessive ataxias, a heterogeneous set of severely disabling neurodegenerative disorders due to loss of function of proteins involved either in mitochondrial/metabolic pathways or DNA repair. Friedreich ataxia, the most common form, is due to partial loss of function of frataxin, a mitochondrial protein involved in iron-sulfur cluster (ISC) biogenesis. Furthermore, the rare X-linked sideroblastic anemia with cerebellar ataxia is caused by mutation in ABCb7, an ATP-binding cassette transporter of the mitochondrial inner membrane necessary for cytosolic ISC export. ISC are versatile co-factors of proteins involved in electron transport, enzyme catalysis and regulation of gene expression. The synthesis and insertion of ISC into apoproteins involve complex machineries that are still poorly understood in the mammalian cell. The objectives of this proposal are: 1) to elucidate ISC biogenesis and metabolism in the mammalian cell, with an emphasis on the role of frataxin and ABCb7; 2) to better understand the molecular pathways that are involved in neuronal dysfunction due to defects in mitochondrial ISC metabolism. These objectives will be accomplished by a multidisciplinary approach combining molecular and biochemical approaches to study the ISC assembly machineries, bioinformatic and proteomic studies to identify new Fe-S proteins, the development and pathological analysis of animal and cellular models to dissect the molecular mechanisms, and transcriptomic analysis to uncover the common pathways among recessive ataxias. A specific focus of the proposal will be the involvement of DNA damage response pathways in neuronal dysfunction, as several DNA repair enzymes have recently been identified as Fe-S proteins and thus might be directly affected by frataxin and ABCb7 deficiency. This proposal should lead to the identification of different pathways for therapeutic intervention for these devastating disorders.
Max ERC Funding
1 449 924 €
Duration
Start date: 2008-07-01, End date: 2013-06-30
Project acronym MYELIN
Project Mechanisms of myelin biogenesis and repair
Researcher (PI) Mikael Simons
Host Institution (HI) MAX-PLANCK-GESELLSCHAFT ZUR FORDERUNG DER WISSENSCHAFTEN EV
Call Details Starting Grant (StG), LS4, ERC-2007-StG
Summary During the development of the central nervous system, specialized glia, oligodendrocytes, extend and wrap their plasma membrane around axons to form tightly packed membrane stacks that provide electrical insulation. Axonal insulation by myelin facilitates rapid nerve conduction and is essential for neuronal metabolism. Damage to the myelin sheath as it for example occurs in multiple sclerosis results in severe neurological disability not only by slowing down nerve conduction, but also as a result of neurodegeneration. Our main goal is to develop strategies to promote remyelination in demyelinating diseases. To realize this goal we need to understand how myelin is formed during normal development. The focus of this project will therefore be on the molecular mechanism of myelination and in particular on the role of neuron-glia communication in this process. We plan to study the mechanisms of myelin membrane growth and test a novel model of membrane extension. We hypothesize that the myelin membrane grows by the lateral diffusion of plasma membrane driven by a tension gradient that is formed by membrane trafficking events. We propose that neurons control this process by regulating the balance of exo- and endocytosis in oligodendrocytes. Furthermore, we would like to test a novel model of myelin membrane assembly, in which we suggest that myelin is formed after a gradual maturation of the plasma membrane that is regulated by neurons and require MBP. We will also investigate the signalling from oligodendrocytes to neurons by analyzing the function of small membrane vesicles, exosomes that we have recently found to be released by oligodendrocytes. Our goal is to understand how these signalling systems act on the cellular machinery that generates myelin. We hope that this approach will not only provide key insights into the development of myelin, but also help us to find new druggable targets for demyelinating diseases.
Summary
During the development of the central nervous system, specialized glia, oligodendrocytes, extend and wrap their plasma membrane around axons to form tightly packed membrane stacks that provide electrical insulation. Axonal insulation by myelin facilitates rapid nerve conduction and is essential for neuronal metabolism. Damage to the myelin sheath as it for example occurs in multiple sclerosis results in severe neurological disability not only by slowing down nerve conduction, but also as a result of neurodegeneration. Our main goal is to develop strategies to promote remyelination in demyelinating diseases. To realize this goal we need to understand how myelin is formed during normal development. The focus of this project will therefore be on the molecular mechanism of myelination and in particular on the role of neuron-glia communication in this process. We plan to study the mechanisms of myelin membrane growth and test a novel model of membrane extension. We hypothesize that the myelin membrane grows by the lateral diffusion of plasma membrane driven by a tension gradient that is formed by membrane trafficking events. We propose that neurons control this process by regulating the balance of exo- and endocytosis in oligodendrocytes. Furthermore, we would like to test a novel model of myelin membrane assembly, in which we suggest that myelin is formed after a gradual maturation of the plasma membrane that is regulated by neurons and require MBP. We will also investigate the signalling from oligodendrocytes to neurons by analyzing the function of small membrane vesicles, exosomes that we have recently found to be released by oligodendrocytes. Our goal is to understand how these signalling systems act on the cellular machinery that generates myelin. We hope that this approach will not only provide key insights into the development of myelin, but also help us to find new druggable targets for demyelinating diseases.
Max ERC Funding
1 290 000 €
Duration
Start date: 2009-01-01, End date: 2012-12-31
Project acronym NANOMAP
Project The Synapse Nanomap
Researcher (PI) Silvio Olivier Rizzoli
Host Institution (HI) UNIVERSITAETSMEDIZIN GOETTINGEN - GEORG-AUGUST-UNIVERSITAET GOETTINGEN - STIFTUNG OEFFENTLICHEN RECHTS
Call Details Starting Grant (StG), LS4, ERC-2007-StG
Summary Stimulated Emission Depletion (STED) microscopy is one of the most important recent developments in light microscopy (Willig et al., 2006, Nature 440:935-9). STED allows for imaging cellular elements with diffraction-unlimited resolution; in practical terms, the resolution (normally limited to ~200-300 nm) is improved down to 30-60 nm. Together with the development of two-color STED microscopy (Donnert et al., 2007, Biophys J. 92:L67-9), this technique allows experimenters to pinpoint the position of various cellular elements with nanometer precision. Obtaining a cellular nanomap is not feasible with conventional light microscopy, due to its low resolution. Electron microscopy cannot be applied, as its labeling efficiency it too low. I propose here to use STED microscopy to characterize the positions of the major components of the synapse. The preparation will be cultured hippocampal neurons, which have numerous small (about one micron in diameter) synaptic nerve terminals. I will determine the locations of synaptic proteins involved in neurotransmitter release, in membrane retrieval and in pre- and post-synaptic active zone structure. Less specialized elements such as the cytoskeleton, mitochondria and endosomes of the synapse will also be investigated. The work will provide answers for a number of questions in the neuroscience field, such as how and where the synaptic vesicles get retrieved, how pre- and post-synaptic active zone elements correlate, and what the role of cytoskeletal elements is in synaptic transmission. The small size and relatively low complexity (compared to whole cells) of the synaptic boutons will allows the work to be completed within a reasonable timeframe. Successful completion of the project will encourage researchers to perform larger scale cellular nano-maps, which would eventually replace the largely erroneous cellular fractionation techniques currently used nowadays to determine the location of various proteins.
Summary
Stimulated Emission Depletion (STED) microscopy is one of the most important recent developments in light microscopy (Willig et al., 2006, Nature 440:935-9). STED allows for imaging cellular elements with diffraction-unlimited resolution; in practical terms, the resolution (normally limited to ~200-300 nm) is improved down to 30-60 nm. Together with the development of two-color STED microscopy (Donnert et al., 2007, Biophys J. 92:L67-9), this technique allows experimenters to pinpoint the position of various cellular elements with nanometer precision. Obtaining a cellular nanomap is not feasible with conventional light microscopy, due to its low resolution. Electron microscopy cannot be applied, as its labeling efficiency it too low. I propose here to use STED microscopy to characterize the positions of the major components of the synapse. The preparation will be cultured hippocampal neurons, which have numerous small (about one micron in diameter) synaptic nerve terminals. I will determine the locations of synaptic proteins involved in neurotransmitter release, in membrane retrieval and in pre- and post-synaptic active zone structure. Less specialized elements such as the cytoskeleton, mitochondria and endosomes of the synapse will also be investigated. The work will provide answers for a number of questions in the neuroscience field, such as how and where the synaptic vesicles get retrieved, how pre- and post-synaptic active zone elements correlate, and what the role of cytoskeletal elements is in synaptic transmission. The small size and relatively low complexity (compared to whole cells) of the synaptic boutons will allows the work to be completed within a reasonable timeframe. Successful completion of the project will encourage researchers to perform larger scale cellular nano-maps, which would eventually replace the largely erroneous cellular fractionation techniques currently used nowadays to determine the location of various proteins.
Max ERC Funding
1 670 000 €
Duration
Start date: 2008-09-01, End date: 2013-08-31