8XGC

Structure of yeast replisome associated with FACT and histone hexamer, Composite map

これはPDB形式変換不可エントリーです。

8XGC の概要

• エントリーDOI: 10.2210/pdb8xgc/pdb
• EMDBエントリー: 38317
• 分子名称: DNA replication licensing factor MCM2, DNA replication complex GINS protein PSF2, DNA replication complex GINS protein PSF3, ... (27 entities in total)
• 機能のキーワード: replisome, fact, histone hexamer, replication
• 由来する生物種: Saccharomyces cerevisiae (brewer's yeast); 詳細
• タンパク質・核酸の鎖数: 29
• 化学式量合計: 2034405.42

構造登録者

Li, N.,Gao, Y.,Yu, D.,Gao, N.,Zhai, Y. (登録日: 2023-12-15, 公開日: 2024-02-14, 最終更新日: 2024-10-30)

主引用文献

Li, N.,Gao, Y.,Zhang, Y.,Yu, D.,Lin, J.,Feng, J.,Li, J.,Xu, Z.,Zhang, Y.,Dang, S.,Zhou, K.,Liu, Y.,Li, X.D.,Tye, B.K.,Li, Q.,Gao, N.,Zhai, Y.
Parental histone transfer caught at the replication fork.
Nature, 627:890-897, 2024

PubMed Abstract: In eukaryotes, DNA compacts into chromatin through nucleosomes. Replication of the eukaryotic genome must be coupled to the transmission of the epigenome encoded in the chromatin. Here we report cryo-electron microscopy structures of yeast (Saccharomyces cerevisiae) replisomes associated with the FACT (facilitates chromatin transactions) complex (comprising Spt16 and Pob3) and an evicted histone hexamer. In these structures, FACT is positioned at the front end of the replisome by engaging with the parental DNA duplex to capture the histones through the middle domain and the acidic carboxyl-terminal domain of Spt16. The H2A-H2B dimer chaperoned by the carboxyl-terminal domain of Spt16 is stably tethered to the H3-H4 tetramer, while the vacant H2A-H2B site is occupied by the histone-binding domain of Mcm2. The Mcm2 histone-binding domain wraps around the DNA-binding surface of one H3-H4 dimer and extends across the tetramerization interface of the H3-H4 tetramer to the binding site of Spt16 middle domain before becoming disordered. This arrangement leaves the remaining DNA-binding surface of the other H3-H4 dimer exposed to additional interactions for further processing. The Mcm2 histone-binding domain and its downstream linker region are nested on top of Tof1, relocating the parental histones to the replisome front for transfer to the newly synthesized lagging-strand DNA. Our findings offer crucial structural insights into the mechanism of replication-coupled histone recycling for maintaining epigenetic inheritance.

PubMed: 38448592
DOI: 10.1038/s41586-024-07152-2

実験手法

ELECTRON MICROSCOPY (3.7 Å)