The Svedberg seminar: Tanja Slotte
May 23 @ 15:15 – 16:15 CEST
Tanja Slotte, Assoc. Prof.
Stockholm University, Sweden
Assoc. Prof. Tanja Slotte is a population geneticist who is interested in the genetic causes and genomic consequences of plant mating system shifts and the evolution of mating system supergenes. She received her PhD from Uppsala University in 2007, followed by a postdoc at University of Toronto. She started her own group at Uppsala University in 2010 and moved to Stockholm University to take up a SciLifeLab Fellow position in 2014. She is currently Associate Professor in Ecological Genomics at Stockholm University.
Title of the seminar: Sequencing the supergene that governs Darwin’s different forms of flower
Supergenes are responsible for a wide variety of balanced polymorphisms in nature, yet our understanding of their origins and evolution remains incomplete. The reciprocal placement of stigmas and anthers in pin and thrum floral morphs of distylous species constitutes an iconic example of a balanced polymorphism governed by a supergene. Recent studies have shown that the Primula distyly S-locus supergene is hemizygous due to structural variation at the supergene. If this genetic architecture is common to other distyly supergenes, it could have major implications for the evolution and loss of distyly. To shed further light on this question we have characterized the genetic architecture and evolution of the distyly supergene in Linum, one of the plant systems where Dawin first described distyly. We have generated multiple high-quality genome assemblies of Linum species as a genomic framework for evolutionary studies. Here, we leverage this framework to identify the distyly S-locus supergene and study its evolution and expression. Our results show that hemizygosity and thrum-specific expression are major features of the Linum distyly supergene, and suggest that the supergene has arisen in a stepwise manner. Our findings demonstrate remarkable convergence in the genetic architecture, origin and evolution of the distyly supergene among systems with independently derived distyly, and shed light on the evolution of the classic supergene that governs Darwin’s “different forms of flowers”.