Sex and genome duplication: studies of biodiversity promotion in wild strawberries

A Division of Life Sciences Faculty Mentorship Colloquium presented by Tia-Lynn Ashman, Department of Biological Sciences, University of Pittsburgh

Wednesday, February 19, 2014
10:00 AM - 11:00 AM
158 Hershey Hall

Abstract

Sexual system and whole genome duplication (polyploidy) are both important drivers of plant biodiversity. Although species with separate sexes are rare in plants this sexual system has evolved in over half of all plant families. Sex chromosome evolution is thought to be a universal feature of separate-sexed organisms but our understanding of the process is heavily influenced by animal systems, the majority of which have ancient sex chromosomes. I will present work on species of wild strawberries (Fragaria, Rosaceae) demonstrating that plants not only provide valuable insight into the earliest stages of sex chromosome evolution from autosomes but also offer key parallels to dynamics seen at later stages in animal systems. A history of hybridization and polyploidization is implicated in the sex chromosome diversity seen in Fragaria, and thus may be a model for other plant lineages. All flowering plants are either ancient or recent polyploids.  As a genus with a world-wide distribution, Fragaria is now also poised to provide insight into the mechanisms by which polyploidy contributes to ecological and evolutionary success.   Integrated projects across two continents will disentangle the role of multiple origins from the intrinsic nature of the polyploid genome in generating biodiversity.

Host: Paul Barber