Filatov Dmitry A
School of Biosciences, University of Birmingham, Edgbaston, UK.
Genetics. 2005 Jun;170(2):975-9. doi: 10.1534/genetics.104.037069. Epub 2005 Apr 16.
The sex chromosomes of dioecious white campion, Silene latifolia (Caryophyllaceae), are of relatively recent origin (10-20 million years), providing a unique opportunity to trace the origin and evolution of sex chromosomes in this genus by comparing closely related Silene species with and without sex chromosomes. Here I demonstrate that four genes that are X-linked in S. latifolia are also linked in nondioecious S. vulgaris, which is consistent with Ohno's (1967) hypothesis that sex chromosomes evolve from a single pair of autosomes. I also report a genetic map for four S. latifolia X-linked genes, SlX1, DD44X, SlX4, and a new X-linked gene SlssX, which encodes spermidine synthase. The order of the genes on the S. latifolia X chromosome and divergence between the homologous X- and Y-linked copies of these genes supports the "evolutionary strata" model, with at least three consecutive expansions of the nonrecombining region on the Y chromosome (NRY) in this plant species.
雌雄异株的宽叶蝇子草（石竹科）的性染色体起源相对较近（1000万至2000万年前），这提供了一个独特的机会，通过比较有无性染色体的近缘蝇子草属物种来追溯该属中性染色体的起源和进化。在此，我证明了在宽叶蝇子草中与X染色体连锁的四个基因在非雌雄异株的普通蝇子草中也连锁，这与大野乾（1967年）的假说是一致的，即性染色体由一对常染色体进化而来。我还报告了宽叶蝇子草四个与X染色体连锁的基因SlX1、DD44X、SlX4以及一个新的与X染色体连锁的基因SlssX（该基因编码亚精胺合成酶）的遗传图谱。宽叶蝇子草X染色体上基因的顺序以及这些基因同源的X连锁和Y连锁拷贝之间的差异支持了“进化层”模型，在该植物物种中Y染色体上的非重组区域（NRY）至少有三次连续扩展。
