9BU7

Cryo-EM Structure of AAV2 Rep68 bound to integration site AAVS1: Insights into the mechanism of DNA melting.

9BU7 の概要

• エントリーDOI: 10.2210/pdb9bu7/pdb
• EMDBエントリー: 44902
• 分子名称: Protein Rep68, DNA (21-MER), PHOSPHOTHIOPHOSPHORIC ACID-ADENYLATE ESTER, ... (5 entities in total)
• 機能のキーワード: aav, protein-dna complex, replication, helicase, aaa+, sf3, dna binding protein, viral protein-dna complex, viral protein/dna
• 由来する生物種: adeno-associated virus 2; 詳細
• タンパク質・核酸の鎖数: 9
• 化学式量合計: 405782.92

構造登録者

Escalante, C.R. (登録日: 2024-05-16, 公開日: 2025-02-12)

主引用文献

Jaiswal, R.,Braud, B.,Hernandez-Ramirez, K.C.,Santosh, V.,Washington, A.,Escalante, C.R.
Cryo-EM structure of AAV2 Rep68 bound to integration site AAVS1: insights into the mechanism of DNA melting.
Nucleic Acids Res., 53:-, 2025

PubMed Abstract: The Rep68 protein from Adeno-Associated Virus (AAV) is a multifunctional SF3 helicase that performs most of the DNA transactions necessary for the viral life cycle. During AAV DNA replication, Rep68 assembles at the origin of replication, catalyzing the DNA melting and nicking reactions during the hairpin rolling replication process to complete the second-strand synthesis of the AAV genome. We report the cryo-electron microscopy structures of Rep68 bound to the adeno-associated virus integration site 1 in different nucleotide-bound states. In the nucleotide-free state, Rep68 forms a heptameric complex around DNA, with three origin-binding domains (OBDs) bound to the Rep-binding element sequence, while three remaining OBDs form transient dimers with them. The AAA+ domains form an open ring without interactions between subunits and DNA. We hypothesize that the heptameric structure is crucial for loading Rep68 onto double-stranded DNA. The ATPγS complex shows that only three subunits associate with the nucleotide, leading to a conformational change that promotes the formation of both intersubunit and DNA interactions. Moreover, three phenylalanine residues in the AAA+ domain induce a steric distortion in the DNA. Our study provides insights into how an SF3 helicase assembles on DNA and provides insights into the DNA melting process.

PubMed: 39883011
DOI: 10.1093/nar/gkaf033

実験手法

ELECTRON MICROSCOPY (3.64 Å)