6TEM

CENP-A nucleosome core particle with 145 base pairs of the Widom 601 sequence by cryo-EM

6TEM の概要

• エントリーDOI: 10.2210/pdb6tem/pdb
• EMDBエントリー: 10822
• 分子名称: Histone H3-like centromeric protein A, Histone H4, Histone H2A, ... (6 entities in total)
• 機能のキーワード: cenp-a nucleosome, protein-dna complex, dna binding protein
• 由来する生物種: Homo sapiens (Human); 詳細
• タンパク質・核酸の鎖数: 10
• 化学式量合計: 199974.75

構造登録者

Boopathi, R.,Danev, R.,Petosa, C.,Bednar, J. (登録日: 2019-11-12, 公開日: 2020-04-08, 最終更新日: 2024-05-15)

主引用文献

Boopathi, R.,Danev, R.,Khoshouei, M.,Kale, S.,Nahata, S.,Ramos, L.,Angelov, D.,Dimitrov, S.,Hamiche, A.,Petosa, C.,Bednar, J.
Phase-plate cryo-EM structure of the Widom 601 CENP-A nucleosome core particle reveals differential flexibility of the DNA ends.
Nucleic Acids Res., 48:5735-5748, 2020

PubMed Abstract: The histone H3 variant CENP-A marks centromeres epigenetically and is essential for mitotic fidelity. Previous crystallographic studies of the CENP-A nucleosome core particle (NCP) reconstituted with a human α-satellite DNA derivative revealed both DNA ends to be highly flexible, a feature important for CENP-A mitotic functions. However, recent cryo-EM studies of CENP-A NCP complexes comprising primarily Widom 601 DNA reported well-ordered DNA ends. Here, we report the cryo-EM structure of the CENP-A 601 NCP determined by Volta phase-plate imaging. The data reveal that one ('left') 601 DNA end is well ordered whereas the other ('right') end is flexible and partly detached from the histone core, suggesting sequence-dependent dynamics of the DNA termini. Indeed, a molecular dynamics simulation of the CENP-A 601 NCP confirmed the distinct dynamics of the two DNA extremities. Reprocessing the image data using two-fold symmetry yielded a cryo-EM map in which both DNA ends appeared well ordered, indicating that such an artefact may inadvertently arise if NCP asymmetry is lost during image processing. These findings enhance our understanding of the dynamic features that discriminate CENP-A from H3 nucleosomes by revealing that DNA end flexibility can be fine-tuned in a sequence-dependent manner.

PubMed: 32313946
DOI: 10.1093/nar/gkaa246

実験手法

ELECTRON MICROSCOPY (3.9 Å)