The chromatin remodeler DDM1 prevents transposon mobility through deposition of histone variant H2A.W
The chromatin remodeler DDM1 prevents transposon mobility through deposition of histone variant H2A.W
复制标题
DOI：
10.1038/s41556-021-00658-1
复制
发表时间：
2021-04-01
影响因子：
21.3
通讯作者：
Berger, Frederic
中科院分区：
文献类型：
--
作者：
Osakabe, Akihisa;Jamge, Bhagyshree;Berger, Frederic
Osakabe等报道了拟南芥中染色质重塑因子DDM 1通过介导H2 A. W沉积使转座因子沉默，移动的转座因子（TE）不仅参与基因组进化，而且威胁基因组的完整性。在健康的细胞中，编码其移动性所必需的所有组分的TE都被特异性沉默，但确切的机制仍然未知。在这里，我们的特点所使用的一个保守的染色质重塑类，防止TE流动性的机制。在拟南芥染色质重塑减少DNA甲基化1（DDM1），我们确定了两个保守的结合结构域的组蛋白变体H2A.W，这标志着植物异染色质。DDM 1是H2 A. W沉积到潜在的移动的TE上所必需和充分的，但不作用于TE片段或宿主蛋白质编码基因。DDM1介导的H2A.W沉积改变了染色质的性质，导致TE沉默，因此阻止了它们的移动性。这种独特的机制提供了对TE与其宿主在进化和疾病背景下的相互作用的见解，并为靶向基因沉默提供了创新策略。
Osakabe et al. report that the chromatin remodeler DDM1 silences transposable elements by mediating H2A.W deposition in Arabidopsis.Mobile transposable elements (TEs) not only participate in genome evolution but also threaten genome integrity. In healthy cells, TEs that encode all of the components that are necessary for their mobility are specifically silenced, yet the precise mechanism remains unknown. Here, we characterize the mechanism used by a conserved class of chromatin remodelers that prevent TE mobility. In the Arabidopsis chromatin remodeler DECREASE IN DNA METHYLATION 1 (DDM1), we identify two conserved binding domains for the histone variant H2A.W, which marks plant heterochromatin. DDM1 is necessary and sufficient for the deposition of H2A.W onto potentially mobile TEs, yet does not act on TE fragments or host protein-coding genes. DDM1-mediated H2A.W deposition changes the properties of chromatin, resulting in the silencing of TEs and, therefore, prevents their mobility. This distinct mechanism provides insights into the interplay between TEs and their host in the contexts of evolution and disease, and potentiates innovative strategies for targeted gene silencing.