Big data in the sex chromosomes of Silene plants and a fungus acting as a plant sex chromosome

Silene latifolia (Caryophyllaceae) is a dioecious plant that has long been used for study on sex chromosomes in plants. The advantage but also disadvantage of S. latifolia as a model system is the size of the Y chromosome that contains an extremely large male-specific region (approx. > 500 Mb). This feature implies that the evolutionary history of sex chromo-somes remains in the S. latifolia Y chromosome, while the size makes analyses esoteric. Another advantage is that plants in the genus Silene show variation in reproductive systems; most are gynodioecy (females and hermaphrodites), which is thought of as an evolutionary status before establishment of dioecy (males and females), with a few hermaphrodites and dioecy, suggesting that the genus Silene may represent an epitome of the sex chromosome evolution. Microbotryum is a biotrophic fungi, whose infection causes masculinization of the female flower, as if the fungus acts as the Y chromo-some. Though the underlying molecular mechanisms remain unknown, recent high-throughput sequence technologies provide many candidate genes for sex determination in plants and sex conversion by the fungus. In this article, I review and introduce studies of the Y chromosome in S. latifolia plant, the evolution of sex chromosomes in the genus Silene, the masculinization of female flowers caused by a fungus infection, and a virus vector that can be used for genetic analysis of the key genes involved in these processes.

研究紹介(Research Reports)