Colin Meiklejohn of Indiana University will speak about “The Evolution of Gene Expression, Sex Chromosomes, and Reproductive Barriers between Species” on June 6 at 2:00 p.m. in Manter Hall Room 103. The seminar will be hosted by Jay Storz. Refreshments will be available beginning at 1:30.
The topic of the seminar:
"Evolutionary changes in gene expression underlie many aspects of phenotypic divergence including the incompatible gene interactions responsible for reproductive isolation between species. My research uses genetic and functional genomic approaches to study the evolution of gene expression and the role of transcriptional regulation in intrinsic post-zygotic incompatibilities. Genetic analysis of divergence in genome-wide patterns of gene expression between closely related Drosophila species reveals substantial differences in the genetic architecture and evolution of cis-regulatory vs. trans-regulatory divergence, and suggests that cis-regulatory substitutions may be over-represented in the evolution of sexually dimorphic phenotypes, while trans-regulatory divergence is an important source of regulatory incompatibilities. Sex chromosomes have repeatedly evolved unique regulatory processes and harbor a disproportionately large number of factors responsible for reproductive isolation between species. I will discuss hypotheses for why hybrid incompatibilities are enriched on sex chromosomes, and present empirical analyses of sex chromosome-specific gene regulation in the Drosophila male germline. Finally, I will present ongoing and future experiments to test the hypothesis that genetic conflict between the sex chromosomes is responsible for the rapid evolution of hybrid male sterility in male heterogametic taxa."