Forming facultative heterochromatin: silencing of an X chromosome in mammalian females

摘要: Compensating for the dosage difference in X-linked genes between male and female mammals involves formation of an extremely stable heterochromatin structure on one two X chromosomes females. The inactive acquires numerous features silent chromatin, including expression a noncoding RNA, switch to late replication, histone modifications, recruitment variant macroH2A DNA hypermethylation. Although induction inactivation differentiating mouse embryonic stem cells suggests that onset each these appears occur sequential manner, it is likely there much more complex interplay different which leads silencing observed somatic cells. Expression untranslated XIST, required cis establishment heterochromatic state. Recent results have started elucidate how Xist controlled, role antisense transcript Tsix.