ジャーナル: Nat Struct Mol Biol / 年: 2024 タイトル: Unwinding of a eukaryotic origin of replication visualized by cryo-EM. 著者: Sarah S Henrikus / Marta H Gross / Oliver Willhoft / Thomas Pühringer / Jacob S Lewis / Allison W McClure / Julia F Greiwe / Giacomo Palm / Andrea Nans / John F X Diffley / Alessandro Costa / 要旨: To prevent detrimental chromosome re-replication, DNA loading of a double hexamer of the minichromosome maintenance (MCM) replicative helicase is temporally separated from DNA unwinding. Upon S-phase ...To prevent detrimental chromosome re-replication, DNA loading of a double hexamer of the minichromosome maintenance (MCM) replicative helicase is temporally separated from DNA unwinding. Upon S-phase transition in yeast, DNA unwinding is achieved in two steps: limited opening of the double helix and topological separation of the two DNA strands. First, Cdc45, GINS and Polε engage MCM to assemble a double CMGE with two partially separated hexamers that nucleate DNA melting. In the second step, triggered by Mcm10, two CMGEs separate completely, eject the lagging-strand template and cross paths. To understand Mcm10 during helicase activation, we used biochemical reconstitution with cryogenic electron microscopy. We found that Mcm10 splits the double CMGE by engaging the N-terminal homo-dimerization face of MCM. To eject the lagging strand, DNA unwinding is started from the N-terminal side of MCM while the hexamer channel becomes too narrow to harbor duplex DNA.
全体 : Complex of Mcm2-7, Cdc45, GINS (Psf1-3, Sld5) DNA polymerase epsi...
全体
名称: Complex of Mcm2-7, Cdc45, GINS (Psf1-3, Sld5) DNA polymerase epsilon (subunit A and B), 19-mer DNA molecule with complementary 7-mer DNA molecule
要素
複合体: Complex of Mcm2-7, Cdc45, GINS (Psf1-3, Sld5) DNA polymerase epsilon (subunit A and B), 19-mer DNA molecule with complementary 7-mer DNA molecule
複合体: DNA replication complex GINS containing Psf1, Psf2, Psf3 and Sld5
タンパク質・ペプチド: DNA replication complex GINS protein PSF1
タンパク質・ペプチド: DNA replication complex GINS protein PSF2
DNA: DNA strand 1
DNA: DNA strand 2
複合体: DNA replication licensing factors MCM2-7
タンパク質・ペプチド: DNA replication licensing factor MCM2
タンパク質・ペプチド: DNA replication licensing factor MCM3
タンパク質・ペプチド: DNA replication licensing factor MCM4
タンパク質・ペプチド: DNA replication licensing factor MCM5
タンパク質・ペプチド: DNA replication licensing factor MCM6
タンパク質・ペプチド: Cell division control protein 45
複合体: DNA polymerase epsilon contains catalytic subunit A and non-catalytic subunit B
タンパク質・ペプチド: DNA replication complex GINS protein SLD5
タンパク質・ペプチド: Minichromosome maintenance protein 10
複合体: DNA
タンパク質・ペプチド: DNA replication licensing factor MCM7
複合体: Cdc45
タンパク質・ペプチド: DNA replication complex GINS protein PSF3
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超分子 #1: Complex of Mcm2-7, Cdc45, GINS (Psf1-3, Sld5) DNA polymerase epsi...
超分子
名称: Complex of Mcm2-7, Cdc45, GINS (Psf1-3, Sld5) DNA polymerase epsilon (subunit A and B), 19-mer DNA molecule with complementary 7-mer DNA molecule タイプ: complex / ID: 1 / 親要素: 0 / 含まれる分子: #1-#14
由来(天然)
生物種: Saccharomyces cerevisiae (パン酵母)
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超分子 #2: DNA replication complex GINS containing Psf1, Psf2, Psf3 and Sld5