1N25

Crystal structure of the SV40 Large T antigen helicase domain

1N25 の概要

• エントリーDOI: 10.2210/pdb1n25/pdb
• 分子名称: Large T Antigen, ZINC ION (2 entities in total)
• 機能のキーワード: helicase domain, 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: 85133.42

構造登録者

Li, D.,Zhao, R.,Lilyestrom, W.,Gai, D.,Zhang, R.,DeCaprio, J.A.,Fanning, E.,Jochimiak, A.,Szakonyi, G.,Chen, X.S. (登録日: 2002-10-21, 公開日: 2003-06-03, 最終更新日: 2024-02-14)

主引用文献

Li, D.,Zhao, R.,Lilyestrom, W.,Gai, D.,Zhang, R.,DeCaprio, J.A.,Fanning, E.,Jochimiak, A.,Szakonyi, G.,Chen, X.S.
Structure of the replicative helicase of the oncoprotein SV40 large tumour antigen
Nature, 423:512-518, 2003

PubMed Abstract: The oncoprotein large tumour antigen (LTag) is encoded by the DNA tumour virus simian virus 40. LTag transforms cells and induces tumours in animals by altering the functions of tumour suppressors (including pRB and p53) and other key cellular proteins. LTag is also a molecular machine that distorts/melts the replication origin of the viral genome and unwinds duplex DNA. LTag therefore seems to be a functional homologue of the eukaryotic minichromosome maintenance (MCM) complex. Here we present the X-ray structure of a hexameric LTag with DNA helicase activity. The structure identifies the p53-binding surface and reveals the structural basis of hexamerization. The hexamer contains a long, positively charged channel with an unusually large central chamber that binds both single-stranded and double-stranded DNA. The hexamer organizes into two tiers that can potentially rotate relative to each other through connecting alpha-helices to expand/constrict the channel, producing an 'iris' effect that could be used for distorting or melting the origin and unwinding DNA at the replication fork.

PubMed: 12774115
DOI: 10.1038/nature01691

実験手法

X-RAY DIFFRACTION (2.8 Å)