Mus81-Eme1 and Rqh1 involvement in processing stalled and collapsed replication forks
Mus81-Eme1 and Rqh1 involvement in processing stalled and collapsed replication forks
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DOI：
10.1074/jbc.m202120200
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发表时间：
2002-09-06
影响因子：
4.8
通讯作者：
Whitby, MC
中科院分区：
文献类型：
--
作者：
Doe, CL;Ahn, JS;Whitby, MC
处理停滞的复制叉和修复崩溃的复制叉是所有生物体的基本功能。在分裂酵母DNA路口停滞复制叉似乎是由Rqh 1 DNA解旋酶或Mus 81-Eme 1内切核酸酶处理。因此，我们表明，超敏反应剂，导致复制叉失速的mus 81，eme 1，和rqh 1突变体被抑制霍利迪交界处resolvase（RusA），是一个mus 81-rqh 1双突变体的合成致死性。重组Mus 81-Eme 1，纯化自大肠杆菌，容易切割复制叉结构，但在体外切割合成霍利迪连接相对较差。从这些数据中，我们提出，Mus 81-Eme 1可以处理停滞的复制叉之前，他们已经回归，形成一个霍利迪结。我们还暗示Mus 81-Eme 1和Rqh 1在修复崩溃的复制叉。在这里，Mus 81-Eme 1和Rqh 1似乎在不同的底物上起作用，因为RusA可以取代Mus 81-Eme 1而不是Rqh 1。
The processing of stalled replication forks and the repair of collapsed replication forks are essential functions in all organisms. In fission yeast DNA junctions at stalled replication forks appear to be processed by either the Rqh1 DNA helicase or Mus81-Eme1 endonuclease. Accordingly, we show that the hypersensitivity to agents that cause replication fork stalling of mus81, eme1, and rqh1 mutants is suppressed by a Holliday junction resolvase (RusA), as is the synthetic lethality of a mus81- rqh1- double mutant. Recombinant Mus81-Eme1, purified from Escherichia coli, readily cleaves replication fork structures but cleaves synthetic Holliday junctions relatively poorly in vitro. From these data we propose that Mus81-Eme1 can process stalled replication forks before they have regressed to form a Holliday junction. We also implicate Mus81-Eme1 and Rqh1 in the repair of collapsed replication forks. Here Mus81-Eme1 and Rqh1 seem to function on different substrates because RusA can substitute for Mus81-Eme1 but not Rqh1.