Project acronym AXIAL.EC
Project PRINCIPLES OF AXIAL POLARITY-DRIVEN VASCULAR PATTERNING
Researcher (PI) Claudio Franco
Host Institution (HI) INSTITUTO DE MEDICINA MOLECULAR JOAO LOBO ANTUNES
Country Portugal
Call Details Starting Grant (StG), LS4, ERC-2015-STG
Summary The formation of a functional patterned vascular network is essential for development, tissue growth and organ physiology. Several human vascular disorders arise from the mis-patterning of blood vessels, such as arteriovenous malformations, aneurysms and diabetic retinopathy. Although blood flow is recognised as a stimulus for vascular patterning, very little is known about the molecular mechanisms that regulate endothelial cell behaviour in response to flow and promote vascular patterning.
Recently, we uncovered that endothelial cells migrate extensively in the immature vascular network, and that endothelial cells polarise against the blood flow direction. Here, we put forward the hypothesis that vascular patterning is dependent on the polarisation and migration of endothelial cells against the flow direction, in a continuous flux of cells going from low-shear stress to high-shear stress regions. We will establish new reporter mouse lines to observe and manipulate endothelial polarity in vivo in order to investigate how polarisation and coordination of endothelial cells movements are orchestrated to generate vascular patterning. We will manipulate cell polarity using mouse models to understand the importance of cell polarisation in vascular patterning. Also, using a unique zebrafish line allowing analysis of endothelial cell polarity, we will perform a screen to identify novel regulators of vascular patterning. Finally, we will explore the hypothesis that defective flow-dependent endothelial polarisation underlies arteriovenous malformations using two genetic models.
This integrative approach, based on high-resolution imaging and unique experimental models, will provide a unifying model defining the cellular and molecular principles involved in vascular patterning. Given the physiological relevance of vascular patterning in health and disease, this research plan will set the basis for the development of novel clinical therapies targeting vascular disorders.
Summary
The formation of a functional patterned vascular network is essential for development, tissue growth and organ physiology. Several human vascular disorders arise from the mis-patterning of blood vessels, such as arteriovenous malformations, aneurysms and diabetic retinopathy. Although blood flow is recognised as a stimulus for vascular patterning, very little is known about the molecular mechanisms that regulate endothelial cell behaviour in response to flow and promote vascular patterning.
Recently, we uncovered that endothelial cells migrate extensively in the immature vascular network, and that endothelial cells polarise against the blood flow direction. Here, we put forward the hypothesis that vascular patterning is dependent on the polarisation and migration of endothelial cells against the flow direction, in a continuous flux of cells going from low-shear stress to high-shear stress regions. We will establish new reporter mouse lines to observe and manipulate endothelial polarity in vivo in order to investigate how polarisation and coordination of endothelial cells movements are orchestrated to generate vascular patterning. We will manipulate cell polarity using mouse models to understand the importance of cell polarisation in vascular patterning. Also, using a unique zebrafish line allowing analysis of endothelial cell polarity, we will perform a screen to identify novel regulators of vascular patterning. Finally, we will explore the hypothesis that defective flow-dependent endothelial polarisation underlies arteriovenous malformations using two genetic models.
This integrative approach, based on high-resolution imaging and unique experimental models, will provide a unifying model defining the cellular and molecular principles involved in vascular patterning. Given the physiological relevance of vascular patterning in health and disease, this research plan will set the basis for the development of novel clinical therapies targeting vascular disorders.
Max ERC Funding
1 618 750 €
Duration
Start date: 2016-09-01, End date: 2022-02-28
Project acronym ContentMAP
Project Contentotopic mapping: the topographical organization of object knowledge in the brain
Researcher (PI) Jorge ALMEIDA
Host Institution (HI) UNIVERSIDADE DE COIMBRA
Country Portugal
Call Details Starting Grant (StG), SH4, ERC-2018-STG
Summary Our ability to recognize an object amongst many others is one of the most important features of the human mind. However, object recognition requires tremendous computational effort, as we need to solve a complex and recursive environment with ease and proficiency. This challenging feat is dependent on the implementation of an effective organization of knowledge in the brain. In ContentMAP I will put forth a novel understanding of how object knowledge is organized in the brain, by proposing that this knowledge is topographically laid out in the cortical surface according to object-related dimensions that code for different types of representational content – I will call this contentotopic mapping. To study this fine-grain topography, I will use a combination of fMRI, behavioral, and neuromodulation approaches. I will first obtain patterns of neural and cognitive similarity between objects, and from these extract object-related dimensions using a dimensionality reduction technique. I will then parametrically manipulate these dimensions with an innovative use of a visual field mapping technique, and test how functional selectivity changes across the cortical surface according to an object’s score on a target dimension. Moreover, I will test the tuning function of these contentotopic maps. Finally, to mirror the complexity of implementing a high-dimensional manifold onto a 2D cortical sheet, I will aggregate the topographies for the different dimensions into a composite map, and develop an encoding model to predict neural signatures for each object. To sum up, ContentMAP will have a dramatic impact in the cognitive sciences by describing how the stuff of concepts is represented in the brain, and providing a complete description of how fine-grain representations and functional selectivity within high-level complex processes are topographically implemented.
Summary
Our ability to recognize an object amongst many others is one of the most important features of the human mind. However, object recognition requires tremendous computational effort, as we need to solve a complex and recursive environment with ease and proficiency. This challenging feat is dependent on the implementation of an effective organization of knowledge in the brain. In ContentMAP I will put forth a novel understanding of how object knowledge is organized in the brain, by proposing that this knowledge is topographically laid out in the cortical surface according to object-related dimensions that code for different types of representational content – I will call this contentotopic mapping. To study this fine-grain topography, I will use a combination of fMRI, behavioral, and neuromodulation approaches. I will first obtain patterns of neural and cognitive similarity between objects, and from these extract object-related dimensions using a dimensionality reduction technique. I will then parametrically manipulate these dimensions with an innovative use of a visual field mapping technique, and test how functional selectivity changes across the cortical surface according to an object’s score on a target dimension. Moreover, I will test the tuning function of these contentotopic maps. Finally, to mirror the complexity of implementing a high-dimensional manifold onto a 2D cortical sheet, I will aggregate the topographies for the different dimensions into a composite map, and develop an encoding model to predict neural signatures for each object. To sum up, ContentMAP will have a dramatic impact in the cognitive sciences by describing how the stuff of concepts is represented in the brain, and providing a complete description of how fine-grain representations and functional selectivity within high-level complex processes are topographically implemented.
Max ERC Funding
1 816 004 €
Duration
Start date: 2019-02-01, End date: 2024-01-31
Project acronym DUNES
Project Sea, Sand and People. An Environmental History of Coastal Dunes
Researcher (PI) Joana FREITAS
Host Institution (HI) Faculdade de letras da Universidade de Lisboa
Country Portugal
Call Details Starting Grant (StG), SH6, ERC-2018-STG
Summary Dunes are now protected environments, being top priority for coastal managers, because of their important role as coastal defences. But, it was not like that in the past.
For centuries dunes were considered unproductive and dangerous. The sand blown by the wind was taken inland, invading fields, silting rivers and destroying villages. In the eighteenth century, a strategy was developed to fight against the dunes: trapping them with trees, with the double purpose of preventing the destruction of arable land and increasing their economic value converting them into forest areas. Different governments, in different countries supported the immobilization of the shifting sands. The strategy, developed in Europe, was taken to other places in the world. These works caused profound changes in vast coastal areas transforming arid landscapes of sandy dunes into green tree forests.
This project aims to explore human-environment relations in coastal areas worldwide, since the eighteenth century until today, through the study of dunes as hybrid landscapes. Based on selected case-studies and comparative approaches, the project will focus on the origins, reasons and means of dunes afforestation; the impacts of the creation of new landscapes to local communities and ecosystems; and the present situation of dunes as coastal defences and rehabilitated environments. The final purpose is to produce an innovative global history of coastal dunes, combining knowledges from both Humanities and Social Sciences and Physical and Life Sciences, which has never been done.
Supported by an interdisciplinary team, this research will result in new developments in the field of the Environmental History studies; provide relevant knowledge considering the need of efficient management solutions to adapt to the expected mean sea level rise; and stimulate environmental citizenship by disseminating the idea that the future of the world coasts depends on today’s actions.
Summary
Dunes are now protected environments, being top priority for coastal managers, because of their important role as coastal defences. But, it was not like that in the past.
For centuries dunes were considered unproductive and dangerous. The sand blown by the wind was taken inland, invading fields, silting rivers and destroying villages. In the eighteenth century, a strategy was developed to fight against the dunes: trapping them with trees, with the double purpose of preventing the destruction of arable land and increasing their economic value converting them into forest areas. Different governments, in different countries supported the immobilization of the shifting sands. The strategy, developed in Europe, was taken to other places in the world. These works caused profound changes in vast coastal areas transforming arid landscapes of sandy dunes into green tree forests.
This project aims to explore human-environment relations in coastal areas worldwide, since the eighteenth century until today, through the study of dunes as hybrid landscapes. Based on selected case-studies and comparative approaches, the project will focus on the origins, reasons and means of dunes afforestation; the impacts of the creation of new landscapes to local communities and ecosystems; and the present situation of dunes as coastal defences and rehabilitated environments. The final purpose is to produce an innovative global history of coastal dunes, combining knowledges from both Humanities and Social Sciences and Physical and Life Sciences, which has never been done.
Supported by an interdisciplinary team, this research will result in new developments in the field of the Environmental History studies; provide relevant knowledge considering the need of efficient management solutions to adapt to the expected mean sea level rise; and stimulate environmental citizenship by disseminating the idea that the future of the world coasts depends on today’s actions.
Max ERC Funding
1 062 330 €
Duration
Start date: 2018-11-01, End date: 2023-10-31
Project acronym RESEAL
Project Epithelial Resealing
Researcher (PI) Antonio Alfredo Coelho Jacinto
Host Institution (HI) FUNDACAO CALOUSTE GULBENKIAN
Country Portugal
Call Details Starting Grant (StG), LS1, ERC-2007-StG
Summary Epithelia have the essential role of acting as a barrier that protects living organisms and its organs from the surrounding milieu. Therefore, it is crucial for epithelial tissues to have robust ways of maintaining its integrity despite the frequent damage caused by normal cell turnover, inflammation and injury. All epithelia have some capacity to repair themselves, however, the wound-healing process differs dramatically between the developmental stage and type of tissue involved. In this project we will focus on investigating the capacity that several simple epithelial tissues have to reseal small discontinuities very rapidly and efficiently. This repair mechanism that we call epithelial resealing is based on the contraction of an actomyosin purse string in the leading edge cells around the wound margin. Epithelial resealing seems to be a fundamental repair mechanism, acting in several types of simple embryonic and adult epithelia, in both vertebrates and invertebrates. The cell biology of epithelial resealing has started to be understood but there are still many open questions and the signalling cascades that regulate this process are largely unknown. We propose to investigate epithelial resealing using a combination of genetics and high resolution live imaging. The Drosophila embryonic epithelium will be our primary model system and we will start by characterizing in detail novel genes involved in resealing that have been identified in a pilot screen previously performed in the laboratory. We will also perform a new RNAi genetic screen based on a very large collections of transgenic lines to completely unravel the signalling network that controls epithelial resealing. In order to investigate how conserved in vertebrates are the epithelial resealing mechanisms, we will establish epithelial wounding assays in zebrafish simple epithelial tissues and we will study, in this vertebrate model system, the molecular mechanisms that we will uncover using Drosophila.
Summary
Epithelia have the essential role of acting as a barrier that protects living organisms and its organs from the surrounding milieu. Therefore, it is crucial for epithelial tissues to have robust ways of maintaining its integrity despite the frequent damage caused by normal cell turnover, inflammation and injury. All epithelia have some capacity to repair themselves, however, the wound-healing process differs dramatically between the developmental stage and type of tissue involved. In this project we will focus on investigating the capacity that several simple epithelial tissues have to reseal small discontinuities very rapidly and efficiently. This repair mechanism that we call epithelial resealing is based on the contraction of an actomyosin purse string in the leading edge cells around the wound margin. Epithelial resealing seems to be a fundamental repair mechanism, acting in several types of simple embryonic and adult epithelia, in both vertebrates and invertebrates. The cell biology of epithelial resealing has started to be understood but there are still many open questions and the signalling cascades that regulate this process are largely unknown. We propose to investigate epithelial resealing using a combination of genetics and high resolution live imaging. The Drosophila embryonic epithelium will be our primary model system and we will start by characterizing in detail novel genes involved in resealing that have been identified in a pilot screen previously performed in the laboratory. We will also perform a new RNAi genetic screen based on a very large collections of transgenic lines to completely unravel the signalling network that controls epithelial resealing. In order to investigate how conserved in vertebrates are the epithelial resealing mechanisms, we will establish epithelial wounding assays in zebrafish simple epithelial tissues and we will study, in this vertebrate model system, the molecular mechanisms that we will uncover using Drosophila.
Max ERC Funding
1 150 000 €
Duration
Start date: 2008-11-01, End date: 2014-10-31
Project acronym RETIMMUNEFUNCTION
Project Role of the proto-oncogene Ret during lymphocyte development and function
Researcher (PI) Jose Henrique Veiga Fernandes
Host Institution (HI) INSTITUTO DE MEDICINA MOLECULAR JOAO LOBO ANTUNES
Country Portugal
Call Details Starting Grant (StG), LS3, ERC-2007-StG
Summary There is growing evidence that molecules classically allocated to nervous system function, such as the neurotrophic factors, are produced by lymphocytes and can also regulate their function. The neurotrophic family includes the GDNF ligands (GFLs), which signal through the RET tyrosine kinase receptor. In humans, mutations of the proto-oncogene Ret have been linked to different diseases, such as cancer and Hirschsprung’s disease. Interestingly, RET expression has been reported in lymphocytes but its functional significance is unclear. We propose to use combined genetic, cellular, and molecular approaches in order to determine, quantify and manipulate the function of RET and GFLs during haematopoiesis and lymphocyte differentiation. In order to achieve this, we will analyse the patterns of RET and GFL expression during haematopoiesis, and in mature lymphocyte sub-sets. By using this strategy we aim to identify differentiation stages where the Ret exerts its role. We then plan to assess the functions of RET and candidate GFLs by studying the impact of Ret and GFL gene ablation. To achieve this, we will study lymphoid cells at different stages of differentiation from mice deficient for Ret or GFLs, and determine the role that these molecules play in key cellular and molecular events during haematopoiesis and immune responses. Since RET is likely to exert its function at various differentiation steps, we plan to use genetically modified mice allowing the conditional deletion of Ret. As a complementary approach, we will generate mice over-expressing RET or constitutively activated RET in a tissue-specific manner, thus mimicking activating mutations of RET associated with cancer. We believe our work, apart from its novelty in the field of immunology, will have a broader impact in other disciplines. Indeed, mechanisms historically ascribed to a specific tissue may be used more generally in order to orchestrate the function and communication among different systems.
Summary
There is growing evidence that molecules classically allocated to nervous system function, such as the neurotrophic factors, are produced by lymphocytes and can also regulate their function. The neurotrophic family includes the GDNF ligands (GFLs), which signal through the RET tyrosine kinase receptor. In humans, mutations of the proto-oncogene Ret have been linked to different diseases, such as cancer and Hirschsprung’s disease. Interestingly, RET expression has been reported in lymphocytes but its functional significance is unclear. We propose to use combined genetic, cellular, and molecular approaches in order to determine, quantify and manipulate the function of RET and GFLs during haematopoiesis and lymphocyte differentiation. In order to achieve this, we will analyse the patterns of RET and GFL expression during haematopoiesis, and in mature lymphocyte sub-sets. By using this strategy we aim to identify differentiation stages where the Ret exerts its role. We then plan to assess the functions of RET and candidate GFLs by studying the impact of Ret and GFL gene ablation. To achieve this, we will study lymphoid cells at different stages of differentiation from mice deficient for Ret or GFLs, and determine the role that these molecules play in key cellular and molecular events during haematopoiesis and immune responses. Since RET is likely to exert its function at various differentiation steps, we plan to use genetically modified mice allowing the conditional deletion of Ret. As a complementary approach, we will generate mice over-expressing RET or constitutively activated RET in a tissue-specific manner, thus mimicking activating mutations of RET associated with cancer. We believe our work, apart from its novelty in the field of immunology, will have a broader impact in other disciplines. Indeed, mechanisms historically ascribed to a specific tissue may be used more generally in order to orchestrate the function and communication among different systems.
Max ERC Funding
1 901 400 €
Duration
Start date: 2008-11-01, End date: 2013-10-31
Project acronym SynapticMitochondria
Project Quality Control and Maintenance of Synaptic Mitochondria
Researcher (PI) Vanessa Alexandra Dos Santos Morais Epifanio
Host Institution (HI) INSTITUTO DE MEDICINA MOLECULAR JOAO LOBO ANTUNES
Country Portugal
Call Details Starting Grant (StG), LS5, ERC-2015-STG
Summary Mitochondria at the synapse have a pivotal role in neurotransmitter release, but almost nothing is known about synaptic mitochondria composition or specific functions. Synaptic mitochondria compared to mitochondria in other cells, need to cope with increased calcium load, more oxidative stress, and high demands of energy generation during synaptic activity. My hypothesis is that synaptic mitochondria have acquired specific mechanisms to manage local stress and that disruption of these mechanisms contributes to neurodegeneration.
How mitochondria sense their dysfunction is unclear. Even more intriguing is the question how they decide whether their failure should lead to removal of the organelle or dismissal of the complete neuron via cell death. We anticipate that these decisions are not only operational during disease, but might constitute a fundamental mechanism relevant for maintenance of synaptic activity and establishment of new synapses.
Recent studies have revealed several genes implicated in neurodegenerative disorders involved in mitochondrial maintenance. However the function of these genes at the synapse, where the initial damage occurs, remains to be clarified. These genes provide excellent starting points to decipher the molecular mechanisms discussed above. Furthermore I propose to use proteomic approaches to identify the protein fingerprint of synaptic mitochondria and to compare them to mitochondria from other tissues. I plan to identify key players of the proposed regulatory pathways involved in intrinsic mitochondria quality control. In a complimentary approach, I will exploit our findings and use in vitro and in vivo experimental approaches to measure mitochondrial function of synaptic versus non-synaptic mitochondria and the relevance of those changes for synaptic function. Our work will unravel the specific properties of synaptic mitochondria and provide much needed insight in their hypothesized predominant role in neurodegenerative disorders.
Summary
Mitochondria at the synapse have a pivotal role in neurotransmitter release, but almost nothing is known about synaptic mitochondria composition or specific functions. Synaptic mitochondria compared to mitochondria in other cells, need to cope with increased calcium load, more oxidative stress, and high demands of energy generation during synaptic activity. My hypothesis is that synaptic mitochondria have acquired specific mechanisms to manage local stress and that disruption of these mechanisms contributes to neurodegeneration.
How mitochondria sense their dysfunction is unclear. Even more intriguing is the question how they decide whether their failure should lead to removal of the organelle or dismissal of the complete neuron via cell death. We anticipate that these decisions are not only operational during disease, but might constitute a fundamental mechanism relevant for maintenance of synaptic activity and establishment of new synapses.
Recent studies have revealed several genes implicated in neurodegenerative disorders involved in mitochondrial maintenance. However the function of these genes at the synapse, where the initial damage occurs, remains to be clarified. These genes provide excellent starting points to decipher the molecular mechanisms discussed above. Furthermore I propose to use proteomic approaches to identify the protein fingerprint of synaptic mitochondria and to compare them to mitochondria from other tissues. I plan to identify key players of the proposed regulatory pathways involved in intrinsic mitochondria quality control. In a complimentary approach, I will exploit our findings and use in vitro and in vivo experimental approaches to measure mitochondrial function of synaptic versus non-synaptic mitochondria and the relevance of those changes for synaptic function. Our work will unravel the specific properties of synaptic mitochondria and provide much needed insight in their hypothesized predominant role in neurodegenerative disorders.
Max ERC Funding
1 300 000 €
Duration
Start date: 2016-09-01, End date: 2022-02-28
Project acronym ZPR
Project The Pancreas Regulome: From causality to prediction of non-coding mutations in human pancreatic diseases
Researcher (PI) Jose Carlos Ribeiro Bessa
Host Institution (HI) INSTITUTO DE BIOLOGIA MOLECULAR E CELULAR-IBMC
Country Portugal
Call Details Starting Grant (StG), LS2, ERC-2015-STG
Summary Several human pancreatic diseases have been characterized, being the diabetes the most common. Like others, this genetic disease is related to disrupted non-coding cis-regulatory elements (CREs) that culminate in altered gene expression. Although Genome Wide Association Studies support this hypothesis, it’s still unclear how mutations on CREs contribute to disease. The translation from the “non-coding code” to phenotype is an exciting and unexplored field that we will approach in this project with the help of the zebrafish as a suitable animal model. We aim to uncover the implications of the disruption of pancreas CREs and how they contribute to diabetes in vivo. For this we will study transcriptional regulation of genes in zebrafish. The similarities between zebrafish and mammal pancreas and the evolutionary conservation of pancreas transcription factors (TF) make it an excellent model to approach and study this disease. In this project we will characterize the zebrafish insulin producing beta-cell regulome, by determining the active CREs in this cell type and their bound TFs. Then we will compare this information with a similar dataset recently available for human beta-cells, to define functional orthologs in these species. Selected CREs will be tested by in vivo gene reporter assays in zebrafish, focusing on those functionally equivalent to human CREs where risk alleles have been associated with diabetes or those regulating genes involved in diabetes. Later these CREs will be mutated in the zebrafish genome to validate their contribution to diabetes. Finally we will translate this to predict new human disease-associated CREs by focusing on the regulatory landscape of diabetes-associated genes, without the need of having countless patients to uncover them. With this project we will create a model system that will allow the identification of new diabetes-associated CREs, which might have a great impact in clinical management of this epidemic disease.
Summary
Several human pancreatic diseases have been characterized, being the diabetes the most common. Like others, this genetic disease is related to disrupted non-coding cis-regulatory elements (CREs) that culminate in altered gene expression. Although Genome Wide Association Studies support this hypothesis, it’s still unclear how mutations on CREs contribute to disease. The translation from the “non-coding code” to phenotype is an exciting and unexplored field that we will approach in this project with the help of the zebrafish as a suitable animal model. We aim to uncover the implications of the disruption of pancreas CREs and how they contribute to diabetes in vivo. For this we will study transcriptional regulation of genes in zebrafish. The similarities between zebrafish and mammal pancreas and the evolutionary conservation of pancreas transcription factors (TF) make it an excellent model to approach and study this disease. In this project we will characterize the zebrafish insulin producing beta-cell regulome, by determining the active CREs in this cell type and their bound TFs. Then we will compare this information with a similar dataset recently available for human beta-cells, to define functional orthologs in these species. Selected CREs will be tested by in vivo gene reporter assays in zebrafish, focusing on those functionally equivalent to human CREs where risk alleles have been associated with diabetes or those regulating genes involved in diabetes. Later these CREs will be mutated in the zebrafish genome to validate their contribution to diabetes. Finally we will translate this to predict new human disease-associated CREs by focusing on the regulatory landscape of diabetes-associated genes, without the need of having countless patients to uncover them. With this project we will create a model system that will allow the identification of new diabetes-associated CREs, which might have a great impact in clinical management of this epidemic disease.
Max ERC Funding
1 497 520 €
Duration
Start date: 2016-06-01, End date: 2021-05-31
