ERC FUNDED PROJECTS

Darwin’s theory of natural selection rests on the principle that fitness variation in natural populations has a heritable component, on which selection acts, thereby leading to evolutionary change. A fundamental and so far unresolved question for the field of evolutionary biology is to identify the genetic loci responsible for this fitness variation, thereby coming closer to an understanding of how variation is maintained in the face of continual selection. One important complicating factor in the search for fitness related genes however is the existence of separate sexes – theoretical expectations and empirical data both suggest that sexually antagonistic genes are common. The phrase “two sexes, one genome” nicely sums up the problem; selection may favour alleles in one sex, even if they have detrimental effects on the fitness of the opposite sex, since it is their net effect across both sexes that determine the likelihood that alleles persist in a population. This theoretical framework raises an interesting, and so far entirely unexplored issue: that in one sex the functional performance of some alleles is predicted to be compromised and this effect may account for some common human diseases and conditions which show genotype-sex interactions. I propose to explore the genetic basis of sex-specific fitness in a model organism in both laboratory and natural conditions and to test whether those genes identified as having sexually antagonistic effects can help explain the incidence of human diseases that display sexual dimorphism in prevalence, age of onset or severity. This multidisciplinary project directly addresses some fundamental unresolved questions in evolutionary biology: the genetic basis and maintenance of fitness variation; the evolution of sexual dimorphism; and aims to provide novel insights into the genetic basis of some common human diseases.

1 500 000 €

Start date: 2012-01-01, End date: 2016-12-31

"Recently through de novo peptide design, we have discovered and presented a new protein structure. This is an all-parallel, 6-helix bundle with a continuous central channel of 0.5 – 0.6 nm diameter. We posit that this is one of a broader class of protein structures that we call the alpha-helical barrels. Here, in three Work Packages, we propose to explore these structures and to develop protein functions within them. First, through a combination of computer-aided design, peptide synthesis and thorough biophysical characterization, we will examine the extents and limits of the alpha-helical-barrel structures. Whilst this is curiosity driven research, it also has practical consequences for the studies that will follow; that is, alpha-helical barrels made from increasing numbers of helices have channels or pores that increase in a predictable way. Second, we will use rational and empirical design approaches to engineer a range of functions within these cavities, including binding capabilities and enzyme-like activities. Finally, and taking the programme into another ambitious area, we will use the alpha-helical barrels to template other folds that are otherwise difficult to design and engineer, notably beta-barrels that insert into membranes to render ion-channel and sensor functions."

2 467 844 €

Start date: 2014-02-01, End date: 2019-01-31

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.

1 991 054 €

Start date: 2015-09-01, End date: 2021-08-31

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.

1 889 995 €

Start date: 2011-10-01, End date: 2017-09-30