PhD studentships in evolutionary theory - Royal Holloway, University of London
The following 2 PhD Projects are on offer at Royal Holloway University of London
Life history and genome architecture
The organization and architecture of the genome has been shaped by natural selection. There is abundant evidence that many genomes contain parts which were acquired from other organisms. Examples are viruses, which have integrated in the genetic material in a cell, and plasmids found in bacteria. The most striking examples are the acquisition of the genomes of organelles such as chromoplasts and mitochondria, which have originated from a fusion of cells.
One fundamental question regarding genome architecture is why, and how, natural selection favours individual genes to cluster into nuclear genomes, and what type of genes were selected to cluster. In this theoretical project we will use mathematical and computer models to investigate this question.
When two genomes are brought together conflicts may arise. For the host cells, the new genome could contain beneficial traits, as well as detrimental traits, for instance bacterial viruses often carry genes which allow bacteria to survive and multiply, but these same viruses can lyse the bacterial cell. For the invading genome there is a tension between fully integrating in their hosts’ genome and optimizing the transmission together with the host but in doing so giving up the possibility of independent transmission.
What we aim to investigate in this project is how selection has acted on these genes, and whether selection would favour genes to cluster into a nuclear genome, or not.
Intra-genomic Conflict and Medical Disorders
Intra-genomic conflict defies the logic of natural selection: why would natural selection favor any gene whose expression reduces the fitness of its host? However intra-genomic conflict has left its signature in many molecular mechanisms. A paradigmatic example of evolution driven by intra-genomic conflict is the case of genomic imprinting where conflict between paternally inherited and maternally inherited genes in the same individual results in silencing of one gene but not the other.
Recently, genomic imprinting (and intra-genomic conflict in general) has been linked to several diseases. For example, deletion of the PWS/AS cluster of imprinted genes causes Prader-Willi syndrome (PWS) when the deletion is paternally inherited but Angelman syndrome (AS) when it is maternally inherited. The clinical phenotype, regarding appetite and activity levels, of children suffering from these syndromes is the reverse: poor sucking and low weight in children with PWS but insatiable appetite and obesity in children with AS.
This intriguing reversal of the clinical phenotype of a deletion is best explained in the light of conflict between genes with different parental origin. In particular, it can be explained when paternally inherited copies favor a greater allocation of maternal resources to offspring than the maternally inherited copy does. We are interested in further exploring the role of intra-genomic conflict in disease. Can we predict the risk of developing diseases caused by genes in conflict? Can we suggest epigenetic modifications that may palliate some symptoms?
Prof. Vincent A.A. Jansen and Dr. Francisco Ubeda
These projects are suitable for candidates with some background or experience in mathematical modeling or simulation at undergraduate level. We are looking for candidates, either with a background in the life sciences, and experience in mathematical or simulation modeling, or for candidates with a background in a quantitative subject (e.g. mathematics, computer science, physics) and an affinity for research in ecology and evolution.
The studentship has a maintenance allowance of £15726 per annum for 3 years and a UK/EU tuition fee waiver. We expect candidates to have a 2.1 or first class degree (or equivalent if not a UK degree). Both studentships will be held in the School of Biological Sciences of Royal Holloway, University of London. The research in the School covers the breadth of biology and hosts a number of theoretical researchers. The School was ranked among the best UK Bioscience Departments in the last research assessment (RAE 2008). The scenic Royal Holloway campus is on the outskirts of London.
If you are interested in applying please contact us informally before the deadline at F.Ubeda(at)rhul.ac.uk or Vincent.jansen(at)rhul.ac.uk. Apply before the 24th of January 2014 (please contact us if an extension to this deadline is helpful) following the link “How to apply” on http://www.rhul.ac.uk/biologicalsciences/prospectivestudents/postgraduat... (projects 8 and 14); get in touch with Tracey Jeffries (Tracey.Jeffries(at)rhul.ac.uk) for any application queries.