The initiation of DNA replication is a highly regulated event in eukaryotic cells to ensure that the entire genome is copied once and only once during S phase. The primary target of cellular regulation of eukaryotic DNA replication initiation is the assembly and activation of the replication fork helicase, the 11-subunit assembly that unwinds DNA at a replication fork. The replication fork helicase, called CMG for Cdc45-Mcm2–7, and GINS, assembles in S phase from the constituent Cdc45, Mcm2–7, and GINS proteins. The assembly and activation of the CMG replication fork helicase during S phase is governed by 2 S-phase specific kinases, CDK and DDK. CDK stimulates the interaction between Sld2, Sld3, and Dpb11, 3 initiation factors that are each required for the initiation of DNA replication. DDK, on the other hand, phosphorylates the Mcm2, Mcm4, and Mcm6 subunits of the Mcm2–7 complex. Sld3 recruits Cdc45 to Mcm2–7 in a manner that depends on DDK, and recent work suggests that Sld3 binds directly to Mcm2–7 and also to single-stranded DNA. Furthermore, recent work demonstrates that Sld3 and its human homolog Treslin substantially stimulate DDK phosphorylation of Mcm2. These data suggest that the initiation factor Sld3/Treslin coordinates the assembly and activation of the eukaryotic replication fork helicase by recruiting Cdc45 to Mcm2–7, stimulating DDK phosphorylation of Mcm2, and binding directly to single-stranded DNA as the origin is melted.
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机译:DNA mam uecfero或人类复制起点的共有序列。控制DNA起始以维持血浆 u00ecdeo圆构建体和适合人类和mam u00ecfero人工染色体载体的DNA的过程或parGene疗法,是在体外或体内控制DNA复制起始和抑制DNA复制的过程,蛋白结合DNA双带。用于复制DNA的反基因,以及使用序列。