+検索条件
-Structure paper
タイトル | CryoEM structures of human CMG-ATPγS-DNA and CMG-AND-1 complexes. |
---|---|
ジャーナル・号・ページ | Nucleic Acids Res, Vol. 48, Issue 12, Page 6980-6995, Year 2020 |
掲載日 | 2020年7月9日 |
著者 | Neil J Rzechorzek / Steven W Hardwick / Vincentius A Jatikusumo / Dimitri Y Chirgadze / Luca Pellegrini / |
PubMed 要旨 | DNA unwinding in eukaryotic replication is performed by the Cdc45-MCM-GINS (CMG) helicase. Although the CMG architecture has been elucidated, its mechanism of DNA unwinding and replisome interactions ...DNA unwinding in eukaryotic replication is performed by the Cdc45-MCM-GINS (CMG) helicase. Although the CMG architecture has been elucidated, its mechanism of DNA unwinding and replisome interactions remain poorly understood. Here we report the cryoEM structure at 3.3 Å of human CMG bound to fork DNA and the ATP-analogue ATPγS. Eleven nucleotides of single-stranded (ss) DNA are bound within the C-tier of MCM2-7 AAA+ ATPase domains. All MCM subunits contact DNA, from MCM2 at the 5'-end to MCM5 at the 3'-end of the DNA spiral, but only MCM6, 4, 7 and 3 make a full set of interactions. DNA binding correlates with nucleotide occupancy: five MCM subunits are bound to either ATPγS or ADP, whereas the apo MCM2-5 interface remains open. We further report the cryoEM structure of human CMG bound to the replisome hub AND-1 (CMGA). The AND-1 trimer uses one β-propeller domain of its trimerisation region to dock onto the side of the helicase assembly formed by Cdc45 and GINS. In the resulting CMGA architecture, the AND-1 trimer is closely positioned to the fork DNA while its CIP (Ctf4-interacting peptide)-binding helical domains remain available to recruit partner proteins. |
リンク | Nucleic Acids Res / PubMed:32453425 / PubMed Central |
手法 | EM (単粒子) |
解像度 | 3.29 - 6.77 Å |
構造データ | EMDB-10619, PDB-6xtx: EMDB-10620: EMDB-10621, PDB-6xty: |
化合物 | ChemComp-ZN: ChemComp-ADP: ChemComp-AGS: ChemComp-MG: |
由来 |
|
キーワード | REPLICATION / CMG / Helicase / ATPase / Replisome |