SPLS Seminar: How mating system impacts siren siRNA Biology

Abstract: The transition from outcrossing to self-fertilization (selfing) is often accompanied by a distinct set of floral morphological changes, which are known as the selfing syndrome. The transition to selfing also profoundly affects the genome, including homozygosity and genomic conflicts. As selfing lineages become more homozygous, selfish genetic elements, such as transposons, lose their ability to spread across different genetic backgrounds. Similarly, kin conflicts, common in outbreeders, diminish when parents and offspring are genetically identical. Recent evidence suggests that many genomic conflicts are regulated epigenetically, leading to the hypothesis of an "epigenomic selfing syndrome." 

This research employs three closely related species with different mating systems, Capsella grandiflora (Cg, an outbreeder), Capsella rubella (Cr, an inbreeder) and Capsella orientalis (Co, an inbreeder), as models. It combines genetic and epigenetic approaches to investigate the hypothesis that there are consistent and predictable changes in epigenomes following the transition to selfing, and that these changes are associated with RNA-directed DNA Methylation (RdDM). In this seminar, I will discuss the difference among three Capsella genomes and initial comparisons of RdDM regulation of their transcriptomes.