Division of Plant Sciences, National Institute of Agrobiological Sciences, Tsukuba, Japan.
Plant Signal Behav. 2010 Jun;5(6):724-6. doi: 10.4161/psb.5.6.11663. Epub 2010 Jun 1.
RNA-directed modification of histones is essential for maintenance of heterochromatin in higher eukaryotes. In plants, cytosine methylation, especially in non-CG sequence contexts, is tightly related to inactive chromatin, but the mechanisms regulating the coexistence of cytosine methylation and repressive histone modification remain obscure. We recently revealed that MORPHEUS' MOLECULE1 (MOM1) of Arabidopsis thaliana silences endogenous loci related to transposons and homologous to the 24-nt siRNAs accumulated in wild type plants, and suggested that MOM1 transduces RNA-directed DNA methylation (RdDM) signals to repressive histone modification. In this addendum, we focus on the involvement of MOM1 in multiple transcriptional gene silencing (TGS) pathways.
RNA 指导的组蛋白修饰对于高等真核生物异染色质的维持至关重要。在植物中，胞嘧啶甲基化，特别是在非 CG 序列背景下，与失活染色质密切相关，但调节胞嘧啶甲基化和抑制性组蛋白修饰共存的机制仍不清楚。我们最近发现拟南芥的 MORPHEUS' MOLECULE1（MOM1）沉默与转座子相关的内源性基因座，并且与在野生型植物中积累的 24-nt siRNAs 同源，并且表明 MOM1 传递 RNA 指导的 DNA 甲基化（RdDM）信号以进行抑制性组蛋白修饰。在这个增刊中，我们重点介绍 MOM1 参与多种转录基因沉默（TGS）途径。
