9PQR

Cryo-EM structure of ATPgammaS-bound Vientovirus FB Rep double hexamer with C6 symmetry

9PQR の概要

• エントリーDOI: 10.2210/pdb9pqr/pdb
• 関連するPDBエントリー: 9PQF 9PQJ 9PQM 9PQO 9PQQ
• EMDBエントリー: 71784 71786 71787 71788 71789
• 分子名称: Replication-associated protein, PHOSPHOTHIOPHOSPHORIC ACID-ADENYLATE ESTER, MAGNESIUM ION (3 entities in total)
• 機能のキーワード: sf3 helicase, dna binding protein, replication, viral protein
• 由来する生物種: Human lung-associated vientovirus FB
• タンパク質・核酸の鎖数: 12
• 化学式量合計: 462617.31

構造登録者

Montermoso, S.,Gupta, K.,Pumroy, R.A.,Moiseenkova-Bell, V.,Bushman, F.D.,Van Duyne, G.D. (登録日: 2025-07-23, 公開日: 2026-02-25, 最終更新日: 2026-03-18)

主引用文献

Montermoso, S.,Gupta, K.,Pumroy, R.A.,Moiseenkova-Bell, V.,Bushman, F.D.,Van Duyne, G.D.
Structures of nucleotide-bound Redondovirus Rep protein link conformation and function.
Plos Pathog., 22:e1013997-e1013997, 2026

PubMed Abstract: Circular Rep-encoding single-stranded DNA (CRESS-DNA) virus Rep proteins are multidomain enzymes that mediate viral DNA rolling-circle replication. Reps nick viral DNA to expose a 3' end for polymerase extension, provide an NTP-dependent helicase activity for DNA unwinding, and join nicked ends to form circular viral genomes. Here, we present the first structures of a Rep protein from the Redondoviridae family, a newly discovered family of human-associated CRESS-DNA viruses that replicates within the oral protozoan Entamoeba gingivalis. Using cryo-EM, we characterized the hexameric structures of a Redondovirus Rep helicase bound with ATPγS, representing the initial ATP-bound state, and with ADP, reflecting the protein state after hydrolysis. The ADP state, but not the ATP state of Rep shows a staircase arrangement of DNA-binding loops that plays a central role in current models for SF3 helicase function. Additionally, we determined a head-to-tail dodecameric structure of ATPγS-bound Rep, in which both the helicase and endonuclease domains are ordered. Conservation of residues involved in stabilizing the dodecamer suggest that this assembly may be functionally relevant for many CRESS-DNA viruses. The positioning of endonuclease domains in the Rep hexamer, combined with our biophysical analyses of Rep oligomerization, provide new insights into Rep function during viral replication.

PubMed: 41779823
DOI: 10.1371/journal.ppat.1013997

実験手法

ELECTRON MICROSCOPY (2.95 Å)