RNF4, a SUMO-targeted ubiquitin E3 ligase, promotes DNA double-strand break repair
RNF4, a SUMO-targeted ubiquitin E3 ligase, promotes DNA double-strand break repair
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DOI：
10.1101/gad.188284.112
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发表时间：
2012-06-01
影响因子：
10.5
通讯作者：
Jackson, Stephen P.
中科院分区：
文献类型：
--
作者：
Galanty, Yaron;Belotserkovskaya, Rimma;Jackson, Stephen P.
蛋白质泛素化和类小泛素化在调节细胞对DNA双链断裂（DSB）的反应中起关键作用。在这里，我们表明，人RNF4，一个小的泛素样修饰剂（SUMO）靶向泛素E3连接酶，招募到DSB的方式需要其SUMO相互作用基序，SUMO E3连接酶PIAS1和PIAS4，和各种DSB响应蛋白。此外，我们发现RNF4耗竭损害DSB位点的泛素加合物形成，并导致持续的组蛋白H2AX磷酸化（γ H2AX）与缺陷的DSB修复，对DSB诱导剂的超敏反应，以及从辐射诱导的细胞周期停滞中延迟恢复。我们确定RNF4调节DSB响应因子MDC1和复制蛋白A（RPA）在DNA损伤位点的营业额，并且RNF4耗尽的细胞不能有效地通过切除的DNA上的同源重组因子BRCA2和RAD 51替换RPA。与先前的数据显示RNF4靶向蛋白质的蛋白酶体相一致，我们表明，蛋白酶体组分PSMD 4被招募到DNA损伤位点的方式需要其泛素相互作用域，RNF4和RNF8。最后，我们确定PSMD4结合MDC1和RPA 1在DNA损伤诱导，RNF4依赖的方式和PSMD4耗尽导致MDC1和γ H2AX持久性照射细胞。因此，RNF4在SUMO和泛素系统之间的十字路口作为DSB响应因子起作用。
Protein ubiquitylation and sumoylation play key roles in regulating cellular responses to DNA double-strand breaks (DSBs). Here, we show that human RNF4, a small ubiquitin-like modifier (SUMO)-targeted ubiquitin E3 ligase, is recruited to DSBs in a manner requiring its SUMO interaction motifs, the SUMO E3 ligases PIAS1 and PIAS4, and various DSB-responsive proteins. Furthermore, we reveal that RNF4 depletion impairs ubiquitin adduct formation at DSB sites and causes persistent histone H2AX phosphorylation (gamma H2AX) associated with defective DSB repair, hypersensitivity toward DSB-inducing agents, and delayed recovery from radiation-induced cell cycle arrest. We establish that RNF4 regulates turnover of the DSB-responsive factors MDC1 and replication protein A (RPA) at DNA damage sites and that RNF4-depleted cells fail to effectively replace RPA by the homologous recombination factors BRCA2 and RAD51 on resected DNA. Consistent with previous data showing that RNF4 targets proteins to the proteasome, we show that the proteasome component PSMD4 is recruited to DNA damage sites in a manner requiring its ubiquitin-interacting domains, RNF4 and RNF8. Finally, we establish that PSMD4 binds MDC1 and RPA1 in a DNA damage-induced, RNF4-dependent manner and that PSMD4 depletion cause MDC1 and gamma H2AX persistence in irradiated cells. RNF4 thus operates as a DSB response factor at the crossroads between the SUMO and ubiquitin systems.