Gene organization of the liverwort Y chromosome reveals distinct sex chromosome evolution in a haploid system
Gene organization of the liverwort Y chromosome reveals distinct sex chromosome evolution in a haploid system
复制标题
DOI：
10.1073/pnas.0609054104
复制
发表时间：
2007-04-10
影响因子：
11.1
通讯作者：
Ohyama, Kanji
中科院分区：
文献类型：
--
作者：
Yamato, Katsuyuki T.;Ishizaki, Kimitsune;Ohyama, Kanji
由于缺乏重组，Y染色体与其他染色体不同。到目前为止，只有一些灵长类动物的Y染色体的完整序列信息是可用的，尽管其他生物，如果蝇的几个物种的信息是可用的。在这里，我们报告了Y染色体的基因组织在雌雄异株多形地草，并提供了一个单倍体有机体的Y染色体的详细视图。在10mb的Y染色体上，鉴定出64个基因，其中14个仅在男性基因组中检测到，并且在生殖器官中表达，而在营养菌体中不表达，表明它们参与了男性生殖功能。Y染色体上的另外40个基因在菌体和男性性器官中表达。这些基因中至少有6个具有分化的x连锁对应物，它们依次在雌性植物的菌体和性器官中表达，这表明这些x和y连锁基因具有基本的细胞功能。这些发现表明，Y染色体和X染色体具有相同的祖先常染色体，并支持单倍体生物体中性染色体上的基本基因比二倍体生物体中更有可能持续存在的预测。
Y chromosomes are different from other chromosomes because of a lack of recombination. Until now, complete sequence information of Y chromosomes has been available only for some primates, although considerable information is available for other organisms, e.g., several species of Drosophila. Here, we report the gene organization of the Y chromosome in the dioecious liverwort Marchantia polymorpha and provide a detailed view of a Y chromosome in a haploid organism. On the 10-Mb Y chromosome, 64 genes are identified, 14 of which are detected only in the male genome and are expressed in reproductive organs but not in vegetative thalli, suggesting their participation in male reproductive functions. Another 40 genes on the Y chromosome are expressed in thalli and male sexual organs. At least six of these genes have diverged X-linked counterparts that are in turn expressed in thalli and sexual organs in female plants, suggesting that these X-and Y-linked genes have essential cellular functions. These findings indicate that the Y and X chromosomes share the same ancestral autosome and support the prediction that in a haploid organism essential genes on sex chromosomes are more likely to persist than in a diploid organism.