The genetics of sperm competition in Drosophila pseudoobscura

Sperm competition is a major source of selection on animal mating systems, and studies of Drosophila have shown that genes expressed in male reproductive tissues are amongst the most rapidly evolving between species. Much is being learned of the function of genes involved in sperm competition in the model species D. melanogaster. Seminal proteins influence male success in sperm competition and can manipulate female reproductive physiology in a sexually antagonistic manner, benefitting the male while harming the female. This can contribute to their rapid evolution. However, little is known of the function of similar loci in different species from other species groups. A recent experimental evolution study in D. pseudoobscura manipulated the levels of selection on males and females, eliminating sexual selection and sperm competition. Several genes have been identified which respond to this manipulation by changing frequency rapidly, and some of them are candidates for a role in mating success and sperm competition. What is their role in mating success and sperm competition success in D. pseudoobscura? Are these genes evolving rapidly because they are favoured in only males or females, or are they sexually antagonistic? Do they also evolve rapidly in natural populations? A PhD studentship is available working in Prof. Mike Ritchie’s laboratory in the University of St Andrews in collaboration with Prof. Rhonda Snook at Stockholm University, Sweden. The student will use CRISPR gene manipulation techniques to develop de novo mutations in the genes we have identified and examine the consequences for male and female mating success. There are numerous ways in which the project can be developed, including other functional analyses of the loci, looking at homologues of other genes identified in studies of D. melanogaster and examining the evolution of the more interesting loci in natural populations and between species. Quantifying the levels of sexually antagonistic selection on natural alleles of the loci could also be of great interest.
The student will receive advanced training in evolutionary and functional genetics, bioinformatics, behavioural and population genetics and will have the opportunity to visit the collaborators laboratory in Stockholm.
For further details contact Prof. Mike Ritchie [Email Address Removed]