Department of Molecular and Cellular Biology, Northwestern University, Chicago, Illinois 60611, USA.
Cold Spring Harb Perspect Biol. 2011 Sep 1;3(9):a003731. doi: 10.1101/cshperspect.a003731.
In most eukaryotes, histone and DNA modifications are responsible for the silencing of genes integrated in heterochromatic sequences, as well as the silencing of pericentromeric repeats and transposable elements themselves. But the mechanisms that guide these modifications to heterochromatin during the cell cycle have been elusive. RNA interference takes advantage of heterochromatic transcription to process small RNAs and recruit enzymes required for both histone and DNA modifications, and is one such mechanism that has been identified. The processes are best understood in fission yeast and plants, but recent work in mammalian cells, especially in the germline, suggests these mechanisms may be highly conserved.
在大多数真核生物中，组蛋白和 DNA 修饰负责沉默整合在异染色质序列中的基因，以及沉默着丝粒重复序列和转座元件本身。但在细胞周期中指导这些修饰进入异染色质的机制一直难以捉摸。RNA 干扰利用异染色质转录来加工小 RNA，并招募组蛋白和 DNA 修饰所需的酶，这是已被确定的一种机制。这些过程在裂殖酵母和植物中得到了较好的理解，但最近在哺乳动物细胞，特别是生殖细胞中的研究表明，这些机制可能高度保守。
