X-chromosome inactivation (XCI) in mammals relies on XIST, a long noncoding transcript that coats and silences the X chromosome in cis. Here researchers from Université Paris Diderot, France report the discovery of a long noncoding RNA, XACT, that is expressed from and coats the active X chromosome specifically in human pluripotent cells. In the absence of XIST, XACT is expressed from both X chromosomes in humans but not in mice, suggesting a unique role for XACT in the control of human XCI initiation.
- Vallot C, Huret C, Lesecque Y, Resch A, Oudrhiri N, Bennaceur-Griscelli A, Duret L, Rougeulle C. (2013) XACT, a long noncoding transcript coating the active X chromosome in human pluripotent cells. Nat Genet 45(3), 239-41. [abstract]