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
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: 2021-08-31
Project acronym SynapticMitochondria
Project Quality Control and Maintenance of Synaptic Mitochondria
Researcher (PI) Vanessa Alexandra Dos Santos Morais Epifânio
Host Institution (HI) INSTITUTO DE MEDICINA MOLECULAR JOAO LOBO ANTUNES
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: 2021-08-31
Project acronym ZPR
Project The Pancreas Regulome: From causality to prediction of non-coding mutations in human pancreatic diseases
Researcher (PI) José Carlos Ribeiro Bessa
Host Institution (HI) INSTITUTO DE BIOLOGIA MOLECULAR E CELULAR-IBMC
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
