5GT3

Crystal structure of nucleosome particle in the presence of human testis-specific histone variant, hTh2b

5GT3 の概要

• エントリーDOI: 10.2210/pdb5gt3/pdb
• 関連するPDBエントリー: 5GSU 5GT0
• 分子名称: Histone H3.1, Histone H4, Histone H2A type 1-D, ... (8 entities in total)
• 機能のキーワード: nucleosome, histone varinats, hth2b, testis-specific, human, structural protein-dna complex, structural protein/dna
• 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: 200230.06

構造登録者

Kumarevel, T.,Sivaraman, P. (登録日: 2016-08-18, 公開日: 2017-02-15, 最終更新日: 2023-11-08)

主引用文献

Padavattan, S.,Thiruselvam, V.,Shinagawa, T.,Hasegawa, K.,Kumasaka, T.,Ishii, S.,Kumarevel, T.
Structural analyses of the nucleosome complexes with human testis-specific histone variants, hTh2a and hTh2b
Biophys. Chem., 221:41-48, 2017

PubMed Abstract: Th2a and Th2b are the testis-specific histone variants highly expressed during spermatogenesis. Approximately 4% of the genome is retained in nucleosomes in mature human sperm, which is enriched at loci of developmental importance. Our recent studies revealed that the mouse histone variant homologs TH2a and TH2b are involved in reprogramming. In the present work, we report three nucleosome structures (NCPs) with human testis-specific histone variants hTh2a and hTh2b, [hGcH (hTh2a-hTh2b-H3-H4), hGcHV1 (hTh2a-H2b-H3-H4) and hGcHV2 (H2a-hTh2b-H3-H4)] and a 146-base pair (bp) duplex DNA fragment at ~3.0Å resolutions. These crystal structures revealed two major changes within the nucleosomes, either with hTh2a, hTh2b or both variants, as compared to the canonical counterpart. First, the H-bonding interactions between the L1-L1' interfaces mediated by the hTh2a/hTh2a' L1-loops are lost. Second, the histone dimer-DNA contacts are considerably reduced, and these changes are localized around ±31 to 35-bp from the nucleosome entry/exit sites. Thus, the modified functional residues at the N- and C-terminal ends of histone variants are responsible for the observed structural changes and regulate the gene expression through specific structural alterations in the chromatin by modulating the chromatin-associated binding proteins.

PubMed: 27992841
DOI: 10.1016/j.bpc.2016.11.013

実験手法

X-RAY DIFFRACTION (2.91 Å)