Project acronym ACHILLES-HEEL
Project Crop resistance improvement by mining natural and induced variation in host accessibility factors
Researcher (PI) Sebastian Schornack
Host Institution (HI) THE CHANCELLOR MASTERS AND SCHOLARS OF THE UNIVERSITY OF CAMBRIDGE
Call Details Starting Grant (StG), LS9, ERC-2014-STG
Summary Increasing crop yield to feed the world is a grand challenge of the 21st century but it is hampered by diseases caused by filamentous plant pathogens. The arms race between pathogen and plant demands constant adjustment of crop germplasm to tackle emerging pathogen races with new virulence features. To date, most crop disease resistance has relied on specific resistance genes that are effective only against a subset of races. We cannot solely rely on classical resistance genes to keep ahead of the pathogens. There is an urgent need to develop approaches based on knowledge of the pathogen’s Achilles heel: core plant processes that are required for pathogen colonization.
Our hypothesis is that disease resistance based on manipulation of host accessibility processes has a higher probability for durability, and is best identified using a broad host-range pathogen. I will employ the filamentous pathogen Phytophthora palmivora to mine plant alleles and unravel host processes providing microbial access in roots and leaves of monocot and dicot plants.
In Aim 1 I will utilize plant symbiosis mutants and allelic variation to elucidate general mechanisms of colonization by filamentous microbes. Importantly, allelic variation will be studied in economically relevant barley and wheat to allow immediate translation into breeding programs.
In Aim 2 I will perform a comparative study of microbial colonization in monocot and dicot roots and leaves. Transcriptional profiling of pathogen and plant will highlight common and contrasting principles and illustrate the impact of differential plant anatomies.
We will challenge our findings by testing beneficial fungi to assess commonalities and differences between mutualist and pathogen colonization. We will use genetics, cell biology and genomics to find suitable resistance alleles highly relevant to crop production and global food security. At the completion of the project, I expect to have a set of genes for resistance breeding.
Summary
Increasing crop yield to feed the world is a grand challenge of the 21st century but it is hampered by diseases caused by filamentous plant pathogens. The arms race between pathogen and plant demands constant adjustment of crop germplasm to tackle emerging pathogen races with new virulence features. To date, most crop disease resistance has relied on specific resistance genes that are effective only against a subset of races. We cannot solely rely on classical resistance genes to keep ahead of the pathogens. There is an urgent need to develop approaches based on knowledge of the pathogen’s Achilles heel: core plant processes that are required for pathogen colonization.
Our hypothesis is that disease resistance based on manipulation of host accessibility processes has a higher probability for durability, and is best identified using a broad host-range pathogen. I will employ the filamentous pathogen Phytophthora palmivora to mine plant alleles and unravel host processes providing microbial access in roots and leaves of monocot and dicot plants.
In Aim 1 I will utilize plant symbiosis mutants and allelic variation to elucidate general mechanisms of colonization by filamentous microbes. Importantly, allelic variation will be studied in economically relevant barley and wheat to allow immediate translation into breeding programs.
In Aim 2 I will perform a comparative study of microbial colonization in monocot and dicot roots and leaves. Transcriptional profiling of pathogen and plant will highlight common and contrasting principles and illustrate the impact of differential plant anatomies.
We will challenge our findings by testing beneficial fungi to assess commonalities and differences between mutualist and pathogen colonization. We will use genetics, cell biology and genomics to find suitable resistance alleles highly relevant to crop production and global food security. At the completion of the project, I expect to have a set of genes for resistance breeding.
Max ERC Funding
1 991 054 €
Duration
Start date: 2015-09-01, End date: 2021-08-31
Project acronym ACMO
Project Systematic dissection of molecular machines and neural circuits coordinating C. elegans aggregation behaviour
Researcher (PI) Mario De Bono
Host Institution (HI) MEDICAL RESEARCH COUNCIL
Call Details Advanced Grant (AdG), LS5, ERC-2010-AdG_20100317
Summary Elucidating how neural circuits coordinate behaviour, and how molecules underpin the properties of individual neurons are major goals of neuroscience. Optogenetics and neural imaging combined with the powerful genetics and well-described nervous system of C. elegans offer special opportunities to address these questions. Previously, we identified a series of sensory neurons that modulate aggregation of C. elegans. These include neurons that respond to O2, CO2, noxious cues, satiety state, and pheromones. We propose to take our analysis to the next level by dissecting how, in mechanistic molecular terms, these distributed inputs modify the activity of populations of interneurons and motoneurons to coordinate group formation. Our strategy is to develop new, highly parallel approaches to replace the traditional piecemeal analysis.
We propose to:
1) Harness next generation sequencing (NGS) to forward genetics, rapidly to identify a molecular ¿parts list¿ for aggregation. Much of the genetics has been done: we have identified almost 200 mutations that inhibit or enhance aggregation but otherwise show no overt phenotype. A pilot study of 50 of these mutations suggests they identify dozens of genes not previously implicated in aggregation. NGS will allow us to molecularly identify these genes in a few months, providing multiple entry points to study molecular and circuitry mechanisms for behaviour.
2) Develop new methods to image the activity of populations of neurons in immobilized and freely moving animals, using genetically encoded indicators such as the calcium sensor cameleon and the voltage indicator mermaid.
This will be the first time a complex behaviour has been dissected in this way. We expect to identify novel conserved molecular and circuitry mechanisms.
Summary
Elucidating how neural circuits coordinate behaviour, and how molecules underpin the properties of individual neurons are major goals of neuroscience. Optogenetics and neural imaging combined with the powerful genetics and well-described nervous system of C. elegans offer special opportunities to address these questions. Previously, we identified a series of sensory neurons that modulate aggregation of C. elegans. These include neurons that respond to O2, CO2, noxious cues, satiety state, and pheromones. We propose to take our analysis to the next level by dissecting how, in mechanistic molecular terms, these distributed inputs modify the activity of populations of interneurons and motoneurons to coordinate group formation. Our strategy is to develop new, highly parallel approaches to replace the traditional piecemeal analysis.
We propose to:
1) Harness next generation sequencing (NGS) to forward genetics, rapidly to identify a molecular ¿parts list¿ for aggregation. Much of the genetics has been done: we have identified almost 200 mutations that inhibit or enhance aggregation but otherwise show no overt phenotype. A pilot study of 50 of these mutations suggests they identify dozens of genes not previously implicated in aggregation. NGS will allow us to molecularly identify these genes in a few months, providing multiple entry points to study molecular and circuitry mechanisms for behaviour.
2) Develop new methods to image the activity of populations of neurons in immobilized and freely moving animals, using genetically encoded indicators such as the calcium sensor cameleon and the voltage indicator mermaid.
This will be the first time a complex behaviour has been dissected in this way. We expect to identify novel conserved molecular and circuitry mechanisms.
Max ERC Funding
2 439 996 €
Duration
Start date: 2011-04-01, End date: 2017-03-31
Project acronym ACTINONSRF
Project MAL: an actin-regulated SRF transcriptional coactivator
Researcher (PI) Richard Treisman
Host Institution (HI) THE FRANCIS CRICK INSTITUTE LIMITED
Call Details Advanced Grant (AdG), LS1, ERC-2010-AdG_20100317
Summary MAL: an actin-regulated SRF transcriptional coactivator
Recent years have seen a revitalised interest in the role of actin in nuclear processes, but the molecular mechanisms involved remain largely unexplored. We will elucidate the molecular basis for the actin-based control of the SRF transcriptional coactivator, MAL. SRF controls transcription through two families of coactivators, the actin-binding MRTFs (MAL, Mkl2), which couple its activity to cytoskeletal dynamics, and the ERK-regulated TCFs (Elk-1, SAP-1, Net). MAL subcellular localisation and transcriptional activity responds to signal-induced changes in G-actin concentration, which are sensed by its actin-binding N-terminal RPEL domain. Members of a second family of RPEL proteins, the Phactrs, also exhibit actin-regulated nucleocytoplasmic shuttling. The proposal addresses the following novel features of actin biology:
¿ Actin as a transcriptional regulator
¿ Actin as a signalling molecule
¿ Actin-binding proteins as targets for regulation by actin, rather than regulators of actin function
We will analyse the sequences and proteins involved in actin-regulated nucleocytoplasmic shuttling, using structural biology and biochemistry to analyse its control by changes in actin-RPEL domain interactions. We will characterise the dynamics of shuttling, and develop reporters for changes in actin-MAL interaction for analysis of pathway activation in vivo. We will identify genes controlling MAL itself, and the balance between the nuclear and cytoplasmic actin pools. The mechanism by which actin represses transcriptional activation by MAL in the nucleus, and its relation to MAL phosphorylation, will be elucidated. Finally, we will map MRTF and TCF cofactor recruitment to SRF targets on a genome-wide scale, and identify the steps in transcription controlled by actin-MAL interaction.
Summary
MAL: an actin-regulated SRF transcriptional coactivator
Recent years have seen a revitalised interest in the role of actin in nuclear processes, but the molecular mechanisms involved remain largely unexplored. We will elucidate the molecular basis for the actin-based control of the SRF transcriptional coactivator, MAL. SRF controls transcription through two families of coactivators, the actin-binding MRTFs (MAL, Mkl2), which couple its activity to cytoskeletal dynamics, and the ERK-regulated TCFs (Elk-1, SAP-1, Net). MAL subcellular localisation and transcriptional activity responds to signal-induced changes in G-actin concentration, which are sensed by its actin-binding N-terminal RPEL domain. Members of a second family of RPEL proteins, the Phactrs, also exhibit actin-regulated nucleocytoplasmic shuttling. The proposal addresses the following novel features of actin biology:
¿ Actin as a transcriptional regulator
¿ Actin as a signalling molecule
¿ Actin-binding proteins as targets for regulation by actin, rather than regulators of actin function
We will analyse the sequences and proteins involved in actin-regulated nucleocytoplasmic shuttling, using structural biology and biochemistry to analyse its control by changes in actin-RPEL domain interactions. We will characterise the dynamics of shuttling, and develop reporters for changes in actin-MAL interaction for analysis of pathway activation in vivo. We will identify genes controlling MAL itself, and the balance between the nuclear and cytoplasmic actin pools. The mechanism by which actin represses transcriptional activation by MAL in the nucleus, and its relation to MAL phosphorylation, will be elucidated. Finally, we will map MRTF and TCF cofactor recruitment to SRF targets on a genome-wide scale, and identify the steps in transcription controlled by actin-MAL interaction.
Max ERC Funding
1 889 995 €
Duration
Start date: 2011-10-01, End date: 2017-09-30
Project acronym ACTOMYOSIN RING
Project Understanding Cytokinetic Actomyosin Ring Assembly Through Genetic Code Expansion, Click Chemistry, DNA origami, and in vitro Reconstitution
Researcher (PI) Mohan Balasubramanian
Host Institution (HI) THE UNIVERSITY OF WARWICK
Call Details Advanced Grant (AdG), LS3, ERC-2014-ADG
Summary The mechanism of cell division is conserved in many eukaryotes, from yeast to man. A contractile ring of filamentous actin and myosin II motors generates the force to bisect a mother cell into two daughters. The actomyosin ring is among the most complex cellular machines, comprising over 150 proteins. Understanding how these proteins organize themselves into a functional ring with appropriate contractile properties remains one of the great challenges in cell biology. Efforts to generate a comprehensive understanding of the mechanism of actomyosin ring assembly have been hampered by the lack of structural information on the arrangement of actin, myosin II, and actin modulators in the ring in its native state. Fundamental questions such as how actin filaments are assembled and organized into a ring remain actively debated. This project will investigate key issues pertaining to cytokinesis in the fission yeast Schizosaccharomyces pombe, which divides employing an actomyosin based contractile ring, using the methods of genetics, biochemistry, cellular imaging, DNA origami, genetic code expansion, and click chemistry. Specifically, we will (1) attempt to visualize actin filament assembly in live cells expressing fluorescent actin generated through synthetic biological approaches, including genetic code expansion and click chemistry (2) decipher actin filament polarity in the actomyosin ring using total internal reflection fluorescence microscopy of labelled dimeric and multimeric myosins V and VI generated through DNA origami approaches (3) address when, where, and how actin filaments for cytokinesis are assembled and organized into a ring and (4) reconstitute actin filament and functional actomyosin ring assembly in permeabilized spheroplasts and in supported bilayers. Success in the project will provide major insight into the mechanism of actomyosin ring assembly and illuminate principles behind cytoskeletal self-organization.
Summary
The mechanism of cell division is conserved in many eukaryotes, from yeast to man. A contractile ring of filamentous actin and myosin II motors generates the force to bisect a mother cell into two daughters. The actomyosin ring is among the most complex cellular machines, comprising over 150 proteins. Understanding how these proteins organize themselves into a functional ring with appropriate contractile properties remains one of the great challenges in cell biology. Efforts to generate a comprehensive understanding of the mechanism of actomyosin ring assembly have been hampered by the lack of structural information on the arrangement of actin, myosin II, and actin modulators in the ring in its native state. Fundamental questions such as how actin filaments are assembled and organized into a ring remain actively debated. This project will investigate key issues pertaining to cytokinesis in the fission yeast Schizosaccharomyces pombe, which divides employing an actomyosin based contractile ring, using the methods of genetics, biochemistry, cellular imaging, DNA origami, genetic code expansion, and click chemistry. Specifically, we will (1) attempt to visualize actin filament assembly in live cells expressing fluorescent actin generated through synthetic biological approaches, including genetic code expansion and click chemistry (2) decipher actin filament polarity in the actomyosin ring using total internal reflection fluorescence microscopy of labelled dimeric and multimeric myosins V and VI generated through DNA origami approaches (3) address when, where, and how actin filaments for cytokinesis are assembled and organized into a ring and (4) reconstitute actin filament and functional actomyosin ring assembly in permeabilized spheroplasts and in supported bilayers. Success in the project will provide major insight into the mechanism of actomyosin ring assembly and illuminate principles behind cytoskeletal self-organization.
Max ERC Funding
2 863 705 €
Duration
Start date: 2015-11-01, End date: 2020-10-31
Project acronym ACTSELECTCONTEXT
Project Action Selection under Contextual Uncertainty: the Role of Learning and Effective Connectivity in the Human Brain
Researcher (PI) Sven Bestmann
Host Institution (HI) UNIVERSITY COLLEGE LONDON
Call Details Starting Grant (StG), LS5, ERC-2010-StG_20091118
Summary In a changing world, one hallmark feature of human behaviour is the ability to learn about the statistics of the environment and use this prior information for action selection. Knowing about a forthcoming event allows for adjusting our actions pre-emptively, which can optimize survival.
This proposal studies how the human brain learns about the uncertainty in the environment, and how this leads to flexible and efficient action selection.
I hypothesise that the accumulation of evidence for future movements through learning reflects a fundamental organisational principle for action control. This explains widely distributed perceptual-, learning-, decision-, and movement-related signals in the human brain. However, little is known about the concerted interplay between brain regions in terms of effective connectivity which is required for flexible behaviour.
My proposal seeks to shed light on this unresolved issue. To this end, I will use i) a multi-disciplinary neuroimaging approach, together with model-based analyses and Bayesian model comparison, adapted to human reaching behaviour as occurring in daily life; and ii) two novel approaches for testing effective connectivity: dynamic causal modelling (DCM) and concurrent transcranial magnetic stimulation-functional magnetic resonance imaging.
My prediction is that action selection relies on effective connectivity changes, which are a function of the prior information that the brain has to learn about.
If true, this will provide novel insight into the human ability to select actions, based on learning about the uncertainty which is inherent in contextual information. This is relevant for understanding action selection during development and ageing, and for pathologies of action such as Parkinson s disease or stroke.
Summary
In a changing world, one hallmark feature of human behaviour is the ability to learn about the statistics of the environment and use this prior information for action selection. Knowing about a forthcoming event allows for adjusting our actions pre-emptively, which can optimize survival.
This proposal studies how the human brain learns about the uncertainty in the environment, and how this leads to flexible and efficient action selection.
I hypothesise that the accumulation of evidence for future movements through learning reflects a fundamental organisational principle for action control. This explains widely distributed perceptual-, learning-, decision-, and movement-related signals in the human brain. However, little is known about the concerted interplay between brain regions in terms of effective connectivity which is required for flexible behaviour.
My proposal seeks to shed light on this unresolved issue. To this end, I will use i) a multi-disciplinary neuroimaging approach, together with model-based analyses and Bayesian model comparison, adapted to human reaching behaviour as occurring in daily life; and ii) two novel approaches for testing effective connectivity: dynamic causal modelling (DCM) and concurrent transcranial magnetic stimulation-functional magnetic resonance imaging.
My prediction is that action selection relies on effective connectivity changes, which are a function of the prior information that the brain has to learn about.
If true, this will provide novel insight into the human ability to select actions, based on learning about the uncertainty which is inherent in contextual information. This is relevant for understanding action selection during development and ageing, and for pathologies of action such as Parkinson s disease or stroke.
Max ERC Funding
1 341 805 €
Duration
Start date: 2011-06-01, End date: 2016-05-31
Project acronym ADaPTIVE
Project Analysing Diversity with a Phenomic approach: Trends in Vertebrate Evolution
Researcher (PI) Anjali Goswami
Host Institution (HI) NATURAL HISTORY MUSEUM
Call Details Starting Grant (StG), LS8, ERC-2014-STG
Summary What processes shape vertebrate diversity through deep time? Approaches to this question can focus on many different factors, from life history and ecology to large-scale environmental change and extinction. To date, the majority of studies on the evolution of vertebrate diversity have focused on relatively simple metrics, specifically taxon counts or univariate measures, such as body size. However, multivariate morphological data provides a more complete picture of evolutionary and palaeoecological change. Morphological data can also bridge deep-time palaeobiological analyses with studies of the genetic and developmental factors that shape variation and must also influence large-scale patterns of evolutionary change. Thus, accurately reconstructing the patterns and processes underlying evolution requires an approach that can fully represent an organism’s phenome, the sum total of their observable traits.
Recent advances in imaging and data analysis allow large-scale study of phenomic evolution. In this project, I propose to quantitatively analyse the deep-time evolutionary diversity of tetrapods (amphibians, reptiles, birds, and mammals). Specifically, I will apply and extend new imaging, morphometric, and analytical tools to construct a multivariate phenomic dataset for living and extinct tetrapods from 3-D scans. I will use these data to rigorously compare extinction selectivity, timing, pace, and shape of adaptive radiations, and ecomorphological response to large-scale climatic shifts across all tetrapod clades. To do so, I will quantify morphological diversity (disparity) and rates of evolution spanning over 300 million years of tetrapod history. I will further analyse the evolution of phenotypic integration by quantifying not just the traits themselves, but changes in the relationships among traits, which reflect the genetic, developmental, and functional interactions that shape variation, the raw material for natural selection.
Summary
What processes shape vertebrate diversity through deep time? Approaches to this question can focus on many different factors, from life history and ecology to large-scale environmental change and extinction. To date, the majority of studies on the evolution of vertebrate diversity have focused on relatively simple metrics, specifically taxon counts or univariate measures, such as body size. However, multivariate morphological data provides a more complete picture of evolutionary and palaeoecological change. Morphological data can also bridge deep-time palaeobiological analyses with studies of the genetic and developmental factors that shape variation and must also influence large-scale patterns of evolutionary change. Thus, accurately reconstructing the patterns and processes underlying evolution requires an approach that can fully represent an organism’s phenome, the sum total of their observable traits.
Recent advances in imaging and data analysis allow large-scale study of phenomic evolution. In this project, I propose to quantitatively analyse the deep-time evolutionary diversity of tetrapods (amphibians, reptiles, birds, and mammals). Specifically, I will apply and extend new imaging, morphometric, and analytical tools to construct a multivariate phenomic dataset for living and extinct tetrapods from 3-D scans. I will use these data to rigorously compare extinction selectivity, timing, pace, and shape of adaptive radiations, and ecomorphological response to large-scale climatic shifts across all tetrapod clades. To do so, I will quantify morphological diversity (disparity) and rates of evolution spanning over 300 million years of tetrapod history. I will further analyse the evolution of phenotypic integration by quantifying not just the traits themselves, but changes in the relationships among traits, which reflect the genetic, developmental, and functional interactions that shape variation, the raw material for natural selection.
Max ERC Funding
1 482 818 €
Duration
Start date: 2015-06-01, End date: 2020-05-31
Project acronym ANXIETY MECHANISMS
Project Neurocognitive mechanisms of human anxiety: identifying and
targeting disrupted function
Researcher (PI) Sonia Jane Bishop
Host Institution (HI) THE CHANCELLOR, MASTERS AND SCHOLARS OF THE UNIVERSITY OF OXFORD
Call Details Starting Grant (StG), LS5, ERC-2010-StG_20091118
Summary Within a 12 month period, 20% of adults will meet criteria for one or more clinical anxiety disorders (ADs). These disorders are hugely disruptive, placing an emotional burden on individuals and their families. While both cognitive behavioural therapy and pharmacological treatment are widely viewed as effective strategies for managing ADs, systematic review of the literature reveals that only 30–45% of patients demonstrate a marked response to treatment (anxiety levels being reduced into the nonaffected range). In addition, a significant proportion of initial responders relapse after treatment is discontinued. There is hence a real and marked need to improve upon current approaches to AD treatment.
One possible avenue for improving response rates is through optimizing initial treatment selection. Specifically, it is possible that certain individuals might respond better to cognitive interventions while others might respond better to pharmacological treatment. Recently it has been suggested that there may be two or more distinct biological pathways disrupted in anxiety. If this is the case, then specification of these pathways may be an important step in predicting which individuals are likely to respond to which treatment. Few studies have focused upon this issue and, in particular, upon identifying neural markers that might predict response to cognitive (as opposed to pharmacological) intervention. The proposed research aims to address this. Specifically, it tests the hypothesis that there are at least two mechanisms disrupted in ADs, one entailing amygdala hyper-responsivity to cues that signal threat, the other impoverished recruitment of frontal regions that support cognitive and emotional regulation.
Two series of functional magnetic resonance imaging experiments will be conducted. These will investigate differences in amygdala and frontal function during (a) attentional processing and (b) fear conditioning. Initial clinical experiments will investigate whether Generalised Anxiety Disorder and Specific Phobia involve differing degrees of disruption to frontal versus amygdala function during these tasks. This work will feed into training studies, the goal being to characterize AD patient subgroups that benefit from cognitive training.
Summary
Within a 12 month period, 20% of adults will meet criteria for one or more clinical anxiety disorders (ADs). These disorders are hugely disruptive, placing an emotional burden on individuals and their families. While both cognitive behavioural therapy and pharmacological treatment are widely viewed as effective strategies for managing ADs, systematic review of the literature reveals that only 30–45% of patients demonstrate a marked response to treatment (anxiety levels being reduced into the nonaffected range). In addition, a significant proportion of initial responders relapse after treatment is discontinued. There is hence a real and marked need to improve upon current approaches to AD treatment.
One possible avenue for improving response rates is through optimizing initial treatment selection. Specifically, it is possible that certain individuals might respond better to cognitive interventions while others might respond better to pharmacological treatment. Recently it has been suggested that there may be two or more distinct biological pathways disrupted in anxiety. If this is the case, then specification of these pathways may be an important step in predicting which individuals are likely to respond to which treatment. Few studies have focused upon this issue and, in particular, upon identifying neural markers that might predict response to cognitive (as opposed to pharmacological) intervention. The proposed research aims to address this. Specifically, it tests the hypothesis that there are at least two mechanisms disrupted in ADs, one entailing amygdala hyper-responsivity to cues that signal threat, the other impoverished recruitment of frontal regions that support cognitive and emotional regulation.
Two series of functional magnetic resonance imaging experiments will be conducted. These will investigate differences in amygdala and frontal function during (a) attentional processing and (b) fear conditioning. Initial clinical experiments will investigate whether Generalised Anxiety Disorder and Specific Phobia involve differing degrees of disruption to frontal versus amygdala function during these tasks. This work will feed into training studies, the goal being to characterize AD patient subgroups that benefit from cognitive training.
Max ERC Funding
1 708 407 €
Duration
Start date: 2011-04-01, End date: 2016-08-31
Project acronym ArtifiCell
Project Synthetic Cell Biology: Designing organelle transport mechanisms
Researcher (PI) James Edward Rothman
Host Institution (HI) UNIVERSITY COLLEGE LONDON
Call Details Advanced Grant (AdG), LS3, ERC-2014-ADG
Summary Imagine being able to design into living cells and organisms de novo vesicle transport mechanisms that do not naturally exist? At one level this is a wild-eyed notion of synthetic biology.
But we contend that this vision can be approached even today, focusing first on the process of exocytosis, a fundamental process that impacts almost every area of physiology. Enough has now been learned about the natural core machinery (as recognized by the award of the 2013 Nobel Prize in Physiology or Medicine to the PI and others) to take highly innovative physics/engineering- and DNA-based approaches to design synthetic versions of the secretory apparatus that could someday open new avenues in genetic medicine.
The central idea is to introduce DNA-based functional equivalents of the core protein machinery that naturally form (coats), target (tethers), and fuse (SNAREs) vesicles. We have already taken first steps by using DNA origami-based templates to produce synthetic phospholipid vesicles and complementary DNA-based tethers to specifically capture these DNA-templated vesicles on targeted bilayers. Others have linked DNA oligonucleotides to trigger vesicle fusion.
The next and much more challenging step is to introduce such processes into living cells. We hope to break this barrier, and in the process start a new field of research into “synthetic exocytosis”, by introducing Peptide-Nucleic Acids (PNAs) of tethers and SNAREs to re-direct naturally-produced secretory vesicles to artificially-programmed targets and provide artificially-programmed regulation. PNAs are chosen mainly because they lack the negatively charged phosphate backbones of DNA, and therefore are more readily delivered into the cell across the plasma membrane. Future steps, would include producing the transport vesicles synthetically within the cell by externally supplied origami-based PNA or similar cages, and - much more speculatively - ultimately using encoded DNA and RNAs to provide these functions.
Summary
Imagine being able to design into living cells and organisms de novo vesicle transport mechanisms that do not naturally exist? At one level this is a wild-eyed notion of synthetic biology.
But we contend that this vision can be approached even today, focusing first on the process of exocytosis, a fundamental process that impacts almost every area of physiology. Enough has now been learned about the natural core machinery (as recognized by the award of the 2013 Nobel Prize in Physiology or Medicine to the PI and others) to take highly innovative physics/engineering- and DNA-based approaches to design synthetic versions of the secretory apparatus that could someday open new avenues in genetic medicine.
The central idea is to introduce DNA-based functional equivalents of the core protein machinery that naturally form (coats), target (tethers), and fuse (SNAREs) vesicles. We have already taken first steps by using DNA origami-based templates to produce synthetic phospholipid vesicles and complementary DNA-based tethers to specifically capture these DNA-templated vesicles on targeted bilayers. Others have linked DNA oligonucleotides to trigger vesicle fusion.
The next and much more challenging step is to introduce such processes into living cells. We hope to break this barrier, and in the process start a new field of research into “synthetic exocytosis”, by introducing Peptide-Nucleic Acids (PNAs) of tethers and SNAREs to re-direct naturally-produced secretory vesicles to artificially-programmed targets and provide artificially-programmed regulation. PNAs are chosen mainly because they lack the negatively charged phosphate backbones of DNA, and therefore are more readily delivered into the cell across the plasma membrane. Future steps, would include producing the transport vesicles synthetically within the cell by externally supplied origami-based PNA or similar cages, and - much more speculatively - ultimately using encoded DNA and RNAs to provide these functions.
Max ERC Funding
3 000 000 €
Duration
Start date: 2015-09-01, End date: 2021-08-31
Project acronym AsthmaPhenotypes
Project Understanding asthma phenotypes: going beyond the atopic/non-atopic paradigm
Researcher (PI) Neil Pearce
Host Institution (HI) LONDON SCHOOL OF HYGIENE AND TROPICAL MEDICINE ROYAL CHARTER
Call Details Advanced Grant (AdG), LS7, ERC-2014-ADG
Summary Fifteen years ago it was widely believed that asthma was an allergic/atopic disease caused by allergen exposure in infancy; this produced atopic sensitization and continued exposure resulted in eosinophilic airways inflammation, bronchial hyper-responsiveness and reversible airflow obstruction. It is now clear that this model is at best incomplete. Less than one-half of asthma cases involve allergic (atopic) mechanisms, and most asthma in low-and-middle income countries is non-atopic. Westernization may be contributing to the global increases in asthma prevalence, but this process appears to involve changes in asthma susceptibility rather than increased exposure to “established” asthma risk factors. Understanding why these changes are occurring is essential in order to halt the growing global asthma epidemic.This will require a combination of epidemiological, clinical and basic science studies in a variety of environments.
A key task is to reclassify asthma phenotypes. These are important to: (i) better understand the aetiological mechanisms of asthma; (ii) identify new causes; and (iii) identify new therapeutic measures. There are major opportunities to address these issues using new techniques for sample collection from the airways (sputum induction, nasal lavage), new methods of analysis (microbiome, epigenetics), and new bioinformatics methods for integrating data from multiple sources and levels. There is an unprecedented potential to go beyond the old atopic/non-atopic categorization of phenotypes.
I will therefore conduct analyses to re-examine and reclassify asthma phenotypes. The key features are the inclusion of: (i) both high and low prevalence centres from both high income countries and low-and-middle income countries; (ii) much more detailed biomarker information than has been used for previous studies of asthma phenotypes; and (iii) new bioinformatics methods for integrating data from multiple sources and levels.
Summary
Fifteen years ago it was widely believed that asthma was an allergic/atopic disease caused by allergen exposure in infancy; this produced atopic sensitization and continued exposure resulted in eosinophilic airways inflammation, bronchial hyper-responsiveness and reversible airflow obstruction. It is now clear that this model is at best incomplete. Less than one-half of asthma cases involve allergic (atopic) mechanisms, and most asthma in low-and-middle income countries is non-atopic. Westernization may be contributing to the global increases in asthma prevalence, but this process appears to involve changes in asthma susceptibility rather than increased exposure to “established” asthma risk factors. Understanding why these changes are occurring is essential in order to halt the growing global asthma epidemic.This will require a combination of epidemiological, clinical and basic science studies in a variety of environments.
A key task is to reclassify asthma phenotypes. These are important to: (i) better understand the aetiological mechanisms of asthma; (ii) identify new causes; and (iii) identify new therapeutic measures. There are major opportunities to address these issues using new techniques for sample collection from the airways (sputum induction, nasal lavage), new methods of analysis (microbiome, epigenetics), and new bioinformatics methods for integrating data from multiple sources and levels. There is an unprecedented potential to go beyond the old atopic/non-atopic categorization of phenotypes.
I will therefore conduct analyses to re-examine and reclassify asthma phenotypes. The key features are the inclusion of: (i) both high and low prevalence centres from both high income countries and low-and-middle income countries; (ii) much more detailed biomarker information than has been used for previous studies of asthma phenotypes; and (iii) new bioinformatics methods for integrating data from multiple sources and levels.
Max ERC Funding
2 348 803 €
Duration
Start date: 2016-01-01, End date: 2020-12-31
Project acronym AVIAN DIMORPHISM
Project The genomic and transcriptomic locus of sex-specific selection in birds
Researcher (PI) Judith Elizabeth Mank
Host Institution (HI) UNIVERSITY COLLEGE LONDON
Call Details Starting Grant (StG), LS8, ERC-2010-StG_20091118
Summary It has long been understood that genes contribute to phenotypes that are then the basis of selection. However, the nature and process of this relationship remains largely theoretical, and the relative contribution of change in gene expression and coding sequence to phenotypic diversification is unclear. The aim of this proposal is to fuse information about sexually dimorphic phenotypes, the mating systems and sexually antagonistic selective agents that shape sexual dimorphism, and the sex-biased gene expression patterns that encode sexual dimorphisms, in order to create a cohesive integrated understanding of the relationship between evolution, the genome, and the animal form. The primary approach of this project is to harnesses emergent DNA sequencing technologies in order to measure evolutionary change in gene expression and coding sequence in response to different sex-specific selection regimes in a clade of birds with divergent mating systems. Sex-specific selection pressures arise in large part as a consequence of mating system, however males and females share nearly identical genomes, especially in the vertebrates where the sex chromosomes house very small proportions of the overall transcriptome. This single shared genome creates sex-specific phenotypes via different gene expression levels in females and males, and these sex-biased genes connect sexual dimorphisms, and the sexually antagonistic selection pressures that shape them, with the regions of the genome that encode them.
The Galloanserae (fowl and waterfowl) will be used to in the proposed project, as this clade combines the necessary requirements of both variation in mating systems and a well-conserved reference genome (chicken). The study species selected from within the Galloanserae for the proposal exhibit a range of sexual dimorphism and sperm competition, and this will be exploited with next generation (454 and Illumina) genomic and transcriptomic data to study the gene expression patterns that underlie sexual dimorphisms, and the evolutionary pressures acting on them. This work will be complemented by the development of mathematical models of sex-specific evolution that will be tested against the gene expression and gene sequence data in order to understand the mechanisms by which sex-specific selection regimes, arising largely from mating systems, shape the phenotype via the genome.
Summary
It has long been understood that genes contribute to phenotypes that are then the basis of selection. However, the nature and process of this relationship remains largely theoretical, and the relative contribution of change in gene expression and coding sequence to phenotypic diversification is unclear. The aim of this proposal is to fuse information about sexually dimorphic phenotypes, the mating systems and sexually antagonistic selective agents that shape sexual dimorphism, and the sex-biased gene expression patterns that encode sexual dimorphisms, in order to create a cohesive integrated understanding of the relationship between evolution, the genome, and the animal form. The primary approach of this project is to harnesses emergent DNA sequencing technologies in order to measure evolutionary change in gene expression and coding sequence in response to different sex-specific selection regimes in a clade of birds with divergent mating systems. Sex-specific selection pressures arise in large part as a consequence of mating system, however males and females share nearly identical genomes, especially in the vertebrates where the sex chromosomes house very small proportions of the overall transcriptome. This single shared genome creates sex-specific phenotypes via different gene expression levels in females and males, and these sex-biased genes connect sexual dimorphisms, and the sexually antagonistic selection pressures that shape them, with the regions of the genome that encode them.
The Galloanserae (fowl and waterfowl) will be used to in the proposed project, as this clade combines the necessary requirements of both variation in mating systems and a well-conserved reference genome (chicken). The study species selected from within the Galloanserae for the proposal exhibit a range of sexual dimorphism and sperm competition, and this will be exploited with next generation (454 and Illumina) genomic and transcriptomic data to study the gene expression patterns that underlie sexual dimorphisms, and the evolutionary pressures acting on them. This work will be complemented by the development of mathematical models of sex-specific evolution that will be tested against the gene expression and gene sequence data in order to understand the mechanisms by which sex-specific selection regimes, arising largely from mating systems, shape the phenotype via the genome.
Max ERC Funding
1 350 804 €
Duration
Start date: 2011-01-01, End date: 2016-07-31
