期刊
BIOESSAYS
卷 40, 期 3, 页码 -出版社
WILEY
DOI: 10.1002/bies.201700208
关键词
CMG helicase; DNA polymerase; DNA replication; origin initiation; replisome
资金
- NIH [GM111472, GM124170, GM115809]
- Van Andel Research Institute
- Howard Hughes Medical Institute
The eukaryotic helicase is an 11-subunit machine containing an Mcm2-7 motor ring that encircles DNA, Cdc45 and the GINS tetramer, referred to as CMG (Cdc45, Mcm2-7, GINS). CMG is built on DNA at origins in two steps. First, two Mcm2-7 rings are assembled around duplex DNA at origins in G1 phase, forming the Mcm2-7 double hexamer. In a second step, in S phase Cdc45 and GINS are assembled onto each Mcm2-7 ring, hence producing two CMGs that ultimately form two replication forks that travel in opposite directions. Here, we review recent findings about CMG structure and function. The CMG unwinds the parental duplex and is also the organizing center of the replisome: it binds DNA polymerases and other factors. EM studies reveal a 20-subunit core replisome with the leading Pol epsilon and lagging Pol alpha-primase on opposite faces of CMG, forming a fundamentally asymmetric architecture. Structural studies of CMG at a replication fork reveal unexpected details of how CMG engages the DNA fork. The structures of CMG and the Mcm2-7 double hexamer on DNA suggest a completely unanticipated process for formation of bidirectional replication forks at origins.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据