MCM core complex / Assembly of the pre-replicative complex / Switching of origins to a post-replicative state / MCM complex binding / nuclear DNA replication / premeiotic DNA replication / replication fork protection complex / pre-replicative complex assembly involved in nuclear cell cycle DNA replication / mitotic DNA replication / Activation of the pre-replicative complex ...MCM core complex / Assembly of the pre-replicative complex / Switching of origins to a post-replicative state / MCM complex binding / nuclear DNA replication / premeiotic DNA replication / replication fork protection complex / pre-replicative complex assembly involved in nuclear cell cycle DNA replication / mitotic DNA replication / Activation of the pre-replicative complex / CMG complex / nuclear pre-replicative complex / Activation of ATR in response to replication stress / DNA replication preinitiation complex / MCM complex / double-strand break repair via break-induced replication / mitotic DNA replication initiation / single-stranded DNA helicase activity / regulation of DNA-templated DNA replication initiation / silent mating-type cassette heterochromatin formation / DNA strand elongation involved in DNA replication / nuclear replication fork / DNA replication origin binding / DNA replication initiation / subtelomeric heterochromatin formation / DNA helicase activity / transcription elongation by RNA polymerase II / helicase activity / heterochromatin formation / single-stranded DNA binding / DNA helicase / chromosome, telomeric region / DNA replication / DNA damage response / chromatin binding / ATP hydrolysis activity / zinc ion binding / nucleoplasm / ATP binding / nucleus / cytoplasm 類似検索 - 分子機能
ジャーナル: Nat Commun / 年: 2017 タイトル: Cryo-EM structure of a licensed DNA replication origin. 著者: Ferdos Abid Ali / Max E Douglas / Julia Locke / Valerie E Pye / Andrea Nans / John F X Diffley / Alessandro Costa / 要旨: Eukaryotic origins of replication are licensed upon loading of the MCM helicase motor onto DNA. ATP hydrolysis by MCM is required for loading and the post-catalytic MCM is an inactive double hexamer ...Eukaryotic origins of replication are licensed upon loading of the MCM helicase motor onto DNA. ATP hydrolysis by MCM is required for loading and the post-catalytic MCM is an inactive double hexamer that encircles duplex DNA. Origin firing depends on MCM engagement of Cdc45 and GINS to form the CMG holo-helicase. CMG assembly requires several steps including MCM phosphorylation by DDK. To understand origin activation, here we have determined the cryo-EM structures of DNA-bound MCM, either unmodified or phosphorylated, and visualize a phospho-dependent MCM element likely important for Cdc45 recruitment. MCM pore loops touch both the Watson and Crick strands, constraining duplex DNA in a bent configuration. By comparing our new MCM-DNA structure with the structure of CMG-DNA, we suggest how the conformational transition from the loaded, post-catalytic MCM to CMG might promote DNA untwisting and melting at the onset of replication.