The Gurdon Institute, Department of Biochemistry, University of Cambridge, Cambridge CB2 1QN, United Kingdom; Genome Integrity Unit, Danish Cancer Society Research Centre, 2100 Copenhagen, Denmark;
The Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark;
Genes Dev. 2014 Sep 15;28(18):1977-82. doi: 10.1101/gad.246272.114. Epub 2014 Sep 4.
RNA metabolism is altered following DNA damage, but the underlying mechanisms are not well understood. Through a 14-3-3 interaction screen for DNA damage-induced protein interactions in human cells, we identified protein complexes connected to RNA biology. These include the nuclear exosome targeting (NEXT) complex that regulates turnover of noncoding RNAs termed promoter upstream transcripts (PROMPTs). We show that the NEXT subunit RBM7 is phosphorylated upon DNA damage by the MAPKAPK2 kinase and establish that this mediates 14-3-3 binding and decreases PROMPT binding. These findings and our observation that cells lacking RBM7 display DNA damage hypersensitivity link PROMPT turnover to the DNA damage response.
RNA 代谢在 DNA 损伤后发生改变,但其中的潜在机制尚不清楚。通过在人类细胞中进行 14-3-3 相互作用筛选以寻找 DNA 损伤诱导的蛋白质相互作用,我们鉴定出与 RNA 生物学相关的蛋白质复合物。这些复合物包括核小体外切酶靶向(NEXT)复合物,该复合物调节称为启动子上游转录物(PROMPTs)的非编码 RNA 的周转。我们发现,MAPKAPK2 激酶在 DNA 损伤后使 NEXT 亚基 RBM7 磷酸化,并证实这介导了 14-3-3 的结合并减少了 PROMPT 的结合。这些发现以及我们观察到缺乏 RBM7 的细胞显示出对 DNA 损伤的敏感性,将 PROMPT 的周转与 DNA 损伤反应联系起来。