Rsx is a metatherian RNA with Xist-like properties in X-chromosome inactivation | |
Article | |
关键词: PRIMORDIAL GERM-CELLS; DOSAGE COMPENSATION; MOUSE; GENE; METHYLATION; EXPRESSION; MAMMALS; | |
DOI : 10.1038/nature11171 | |
来源: SCIE |
【 摘 要 】
In female (XX) mammals, one of the two X chromosomes is inactivated to ensure an equal dose of X-linked genes with males (XY)(1). X-chromosome inactivation in eutherian mammals is mediated by the non-coding RNA Xist(2). Xist is not found in metatherians(3) (marsupials), and how X-chromosome inactivation is initiated in these mammals has been the subject of speculation for decades(4). Using the marsupial Monodelphis domestica, here we identify Rsx (RNA-on-the-silent X), an RNA that has properties consistent with a role in X-chromosome inactivation. Rsx is a large, repeat-rich RNA that is expressed only in females and is transcribed from, and coats, the inactive X chromosome. In female germ cells, in which both X chromosomes are active, Rsx is silenced, linking Rsx expression to X-chromosome inactivation and reactivation. Integration of an Rsx transgene on an autosome in mouse embryonic stem cells leads to gene silencing in cis. Our findings permit comparative studies of X-chromosome inactivation in mammals and pose questions about the mechanisms by which X-chromosome inactivation is achieved in eutherians.
【 授权许可】
Free