Plant & Animal Genomes XIII Conference Plant & Animal Genomes XIII ConferenceJanuary 15-19, 2005
Town & Country Convention Center
San Diego, CA
Sex chromosomes have evolved in both animal and plant kingdoms independently and repeatedly. Surprisingly, the presence of well-established sex chromosomes in dioecious plants is rare. Silene latifolia is the basic plant model to study sex determination and sex chromosome evolution. In contrast to mammalian sex chromosomes, which have been evolving for at least 250–300 million years (My), the sex chromosomes of S. latifolia are 10 times younger. We have improved FISH strategy for differentiating the sex chromosomes of S. latifolia by chromosome painting. This new approach represents a quick tool to compare organization of plant genomes. We have also generated new sex linked markers by constructing and screening a sample bacterial artificial chromosome (BAC) library for appropriate FISH probes. The results show that divergence of the sex chromosomes of S. latifolia is already in process and degeneration of the Y chromosome by accumulation of specific sequences has begun.