RRC ID 73668
Author Miyazawa-Onami M, Araki H, Tanaka S.
Title Pre-initiation complex assembly functions as a molecular switch that splits the Mcm2-7 double hexamer.
Journal EMBO Rep
Abstract Initiation of chromosomal DNA replication in eukaryotes involves two steps: licensing and firing. In licensing, a core component of the replicative helicase, the Mcm2-7 complex, is loaded onto replication origins as an inactive double hexamer, which is activated in the firing step by firing factors. A reaction intermediate called the pre-initiation complex (pre-IC) has been proposed to assemble transiently during firing, but the existence of the pre-IC has not yet been confirmed. Here, we show, by systematic chromatin immunoprecipitation, that a distinct intermediate that fits the definition of the pre-IC assembles during firing in the budding yeast Saccharomyces cerevisiae Pre-IC assembly is observed in the absence of Mcm10, one of the firing factors, and is mutually dependent on all the firing factors whose association to replication origins is triggered by cyclin-dependent kinase. In the pre-IC, the Mcm2-7 double hexamer is separated into single hexamers, as in the active helicase. Our data indicate that pre-IC assembly functions as an all-or-nothing molecular switch that splits the Mcm2-7 double hexamer.
Volume 18(10)
Pages 1752-1761
Published 2017-10-1
DOI 10.15252/embr.201744206
PII embr.201744206
PMID 28818838
PMC PMC5623835
MeSH Cell Cycle Proteins / genetics Cell Cycle Proteins / metabolism DNA Replication* DNA, Fungal / genetics DNA-Binding Proteins / genetics DNA-Binding Proteins / metabolism Immunoprecipitation Minichromosome Maintenance Proteins / chemistry* Minichromosome Maintenance Proteins / genetics Minichromosome Maintenance Proteins / metabolism* Replication Origin Saccharomyces cerevisiae / genetics* Saccharomyces cerevisiae / metabolism Saccharomyces cerevisiae Proteins / chemistry Saccharomyces cerevisiae Proteins / economics Saccharomyces cerevisiae Proteins / genetics Saccharomyces cerevisiae Proteins / metabolism*
IF 7.497
Yeast BY28997(YST1351) BY28998(YST1400) BY28266(YST2199) BY28999(YST2204) BY29000(YST2211) BY29001(YST2359) BY28267(YST2363) BY28270(YST2393) BY28271(YST2395) BY28273(YST2397)