Replication-dependent cytotoxicity and Spartan-mediated repair of trapped PARP1?DNA complexes
Replication-dependent cytotoxicity and Spartan-mediated repair of trapped PARP1?DNA complexes
复制标题
复制依赖性细胞毒性和 Spartan 介导的 PARP1?DNA 复合物修复
DOI：
10.1093/nar/gkab777
复制
发表时间：
2021
影响因子：
14.9
通讯作者：
Pommier Yves
中科院分区：
文献类型：
--
作者：
Saha Liton Kumar;Murai Yasuhisa;Saha Sourav;Jo Ukhyun;Tsuda Masataka;Takeda Shunichi;Pommier Yves
聚（ADP-核糖）聚合酶抑制剂（PARP）的抗肿瘤活性已被归因于PARP捕获，其存在于紧密的DNA-蛋白质复合物中。在这里，我们证明了talazoparib和olaparib的细胞毒性是由DNA复制引起的。为了阐明与人TK 6和鸡DT 40淋巴母细胞中复制相关的PARP 1-DNA复合物的修复，我们探索了Spartan（SPRTN）的作用，Spartan是一种与DNA复制相关的金属蛋白酶，可去除形成DPC的蛋白质。我们发现SPRTN缺陷细胞对talazoparib和olaparib超敏，但对veliparib（一种弱PARP捕获剂）不敏感。SPRTN缺陷细胞在talazoparib和olaparib处理后表现出捕获的PARP 1的延迟清除和增加的复制叉停滞。我们还发现SPRTN与PARP 1相互作用，并形成与复制型细胞分裂周期45蛋白（CDC 45）共定位的核灶，以响应Talazoparib。此外，SPRTN是去泛素化和上位性的，具有对talazoparib的响应的跨病变合成（TLS）。我们的研究结果表明，SPRTN被招募到S期捕获PARP 1，以协助PARP 1-DNA复合物的切除和复制旁路。
The antitumor activity of poly(ADP-ribose) polymerase inhibitors (PARPis) has been ascribed to PARP trapping, which consists in tight DNA–protein complexes. Here we demonstrate that the cytotoxicity of talazoparib and olaparib results from DNA replication. To elucidate the repair of PARP1–DNA complexes associated with replication in human TK6 and chicken DT40 lymphoblastoid cells, we explored the role of Spartan (SPRTN), a metalloprotease associated with DNA replication, which removes proteins forming DPCs. We find that SPRTN-deficient cells are hypersensitive to talazoparib and olaparib, but not to veliparib, a weak PARP trapper. SPRTN-deficient cells exhibit delayed clearance of trapped PARP1 and increased replication fork stalling upon talazoparib and olaparib treatment. We also show that SPRTN interacts with PARP1 and forms nuclear foci that colocalize with the replicative cell division cycle 45 protein (CDC45) in response to talazoparib. Additionally, SPRTN is deubiquitinated and epistatic with translesion synthesis (TLS) in response to talazoparib. Our results demonstrate that SPRTN is recruited to trapped PARP1 in S-phase to assist in the excision and replication bypass of PARP1–DNA complexes.