1SVO

Structure of SV40 large T antigen helicase domain

1SVO の概要

• エントリーDOI: 10.2210/pdb1svo/pdb
• 分子名称: large T antigen, ZINC ION (3 entities in total)
• 機能のキーワード: aaa+ fold, viral protein
• 由来する生物種: Simian virus 40
• 細胞内の位置: Host nucleus: P03070
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 87213.66

構造登録者

Gai, D.,Zhao, R.,Finkielstein, C.V.,Chen, X.S. (登録日: 2004-03-29, 公開日: 2004-10-19, 最終更新日: 2024-11-06)

主引用文献

Gai, D.,Zhao, R.,Li, D.,Finkielstein, C.V.,Chen, X.S.
Mechanisms of conformational change for a replicative hexameric helicase of SV40 large tumor antigen.
Cell(Cambridge,Mass.), 119:47-60, 2004

PubMed Abstract: The large tumor antigen (LTag) of simian virus 40, an AAA(+) protein, is a hexameric helicase essential for viral DNA replication in eukaryotic cells. LTag functions as an efficient molecular machine powered by ATP binding and hydrolysis for origin DNA melting and replication fork unwinding. To understand how ATP binding and hydrolysis are coupled to conformational changes, we have determined high-resolution structures ( approximately 1.9 A) of LTag hexamers in distinct nucleotide binding states. The structural differences of LTag in various nucleotide states detail the molecular mechanisms of conformational changes triggered by ATP binding/hydrolysis and reveal a potential mechanism of concerted nucleotide binding and hydrolysis. During these conformational changes, the angles and orientations between domains of a monomer alter, creating an "iris"-like motion in the hexamer. Additionally, six unique beta hairpins on the channel surface move longitudinally along the central channel, possibly serving as a motor for pulling DNA into the LTag double hexamer for unwinding.

PubMed: 15454080
DOI: 10.1016/j.cell.2004.09.017

実験手法

X-RAY DIFFRACTION (2.6 Å)