A curious new role for MRN in Schizosaccharomyces pombe non-homologous end-joining.
A curious new role for MRN in Schizosaccharomyces pombe non-homologous end-joining.
复制标题
MRN 在粟酒裂殖酵母非同源末端连接中的一个奇怪的新作用。
DOI：
10.1007/s00294-017-0760-1
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发表时间：
2018
期刊：
影响因子：
2.5
通讯作者：
Li,Yanhui
中科院分区：
文献类型：
--
作者：
Runge,KurtW;Li,Yanhui
染色体断裂可以通过几种修复过程来修复，包括一种称为非同源末端连接（NHEJ）的修复过程，其中两个断裂的末端连接在一起，损失0-5 bp的DNA。芽殖酵母Saccharomyces gulae中切割DNA末端的NHEJ的蛋白质需求包括其Mre 11-Rad 50-Nbs 1（MRN）复合物的版本。相比之下，裂殖酵母和哺乳动物细胞在这一过程中不需要MRN.最近在粟酒裂殖酵母中的工作使用转座子切除来产生由DNA发夹加帽的断裂，其必须打开以产生可连接的末端。粟酒裂殖酵母通过NHEJ反应进行修复，现在需要MRN。令人惊讶的是，野生型细胞和缺乏核酸酶活性的MRN突变体显示出相同水平的切除。这些遗传结果表明，MRN招募了一种未知的发夹开放核酸酶，用于这种不寻常的NHEJ反应。
Chromosomal breaks can be healed by several repair processes, including one called non-homologous end-joining (NHEJ) where the two broken ends are ligated together with a loss of 0–5 bp of DNA. The protein requirements for NHEJ of cut DNA ends in the budding yeastSaccharomyces cerevisiaeinclude its version of the Mre11–Rad50–Nbs1 (MRN) complex. In contrast, the fission yeastSchizosaccharomyces pombeand mammalian cells do not require MRN for this process. Recent work inS. pombeused transposon excision to generate breaks that were capped by DNA hairpins, which must be opened to produce ligatable ends. Repair inS. pombewas through an NHEJ reaction that now requires MRN. Surprisingly, wild type cells and MRN mutants that lack nuclease activity showed the same levels of excision. These genetic results suggest that MRN recruits an unknown hairpin-opening nuclease for this unusual NHEJ reaction.