在这里，研究人员发现TTF2 ATP酶是一种新型的磷酸化受体，在有丝分裂期间结合TRAIP上的一个保守磷酸化位点。TTF2偶对将TRAIP磷酸化为复制体中的DNA聚合酶ε (Pol ε)，导致TRAIP泛素化CDC45-MCM-GINS （CMG）解旋酶。这触发了有丝分裂复制体的解体，以及产生姐妹染色单体交换的修复途径，支持了叉裂如何促进哺乳动物细胞中未充分复制位点分离的模型。
据了解，哺乳动物细胞经常在DNA复制完成之前进入有丝分裂，需要快速处理未复制的位点以促进染色体分离。TRAIP泛素连接酶在有丝分裂过程中诱导复制体解体，触发DNA复制叉的分裂。到目前为止，调控TRAIP和加工断裂DNA复制叉的机制尚不清楚。
附：英文原文
Title: TTF2 processes sites of incomplete DNA replication during mitosis via sister-chromatid exchanges
Author: Ryo Fujisawa, Karim P. M. Labib
Issue&Volume: 2026-07-02
Abstract: Mammalian cells frequently enter mitosis before DNA replication has finished, necessitating the rapid processing of unreplicated loci to facilitate chromosome segregation. The TRAIP ubiquitin ligase induces replisome disassembly during mitosis, triggering the cleavage of DNA replication forks. Until now, the mechanisms that regulate TRAIP and process cleaved DNA replication forks were unclear. Here we show that the TTF2 ATPase is a new type of phospho-receptor that binds a conserved phosphorylation site on TRAIP during mitosis. TTF2 couples phosphorylated TRAIP to DNA polymerase epsilon (Pol ε) in the replisome, leading TRAIP to ubiquitylate the CDC45-MCM-GINS (CMG) helicase. This triggers mitotic replisome disassembly, and a repair pathway that produces sister-chromatid exchanges, supporting a model for how fork cleavage promotes the segregation of under-replicated loci in mammalian cells.
DOI: aeh2300
Source: https://www.science.org/doi/10.1126/science.aeh2300