8FMA

Nodavirus RNA replication proto-crown, detergent-solubliized C11 multimer

8FMA の概要

• エントリーDOI: 10.2210/pdb8fma/pdb
• EMDBエントリー: 29290
• 分子名称: RNA-directed RNA polymerase (1 entity in total)
• 機能のキーワード: nodavirus rna replication and rna capping complex, outer mitochondrial membrane protein complex, viral protein
• 由来する生物種: Flock House virus
• タンパク質・核酸の鎖数: 22
• 化学式量合計: 2507924.89

構造登録者

Zhan, H.,Unchwaniwala, N.,Rebolledo Viveros, A.,Pennington, J.,Horswill, M.,Broadberry, R.,Myers, J.,den Boon, J.,Grant, T.,Ahlquist, P. (登録日: 2022-12-22, 公開日: 2023-02-01, 最終更新日: 2024-06-19)

主引用文献

Zhan, H.,Unchwaniwala, N.,Rebolledo-Viveros, A.,Pennington, J.,Horswill, M.,Broadberry, R.,Myers, J.,den Boon, J.A.,Grant, T.,Ahlquist, P.
Nodavirus RNA replication crown architecture reveals proto-crown precursor and viral protein A conformational switching.
Proc.Natl.Acad.Sci.USA, 120:e2217412120-e2217412120, 2023

PubMed Abstract: Positive-strand RNA viruses replicate their genomes in virus-induced membrane vesicles, and the resulting RNA replication complexes are a major target for virus control. Nodavirus studies first revealed viral RNA replication proteins forming a 12-fold symmetric "crown" at the vesicle opening to the cytosol, an arrangement recently confirmed to extend to distantly related alphaviruses. Using cryoelectron microscopy (cryo-EM), we show that mature nodavirus crowns comprise two stacked 12-mer rings of multidomain viral RNA replication protein A. Each ring contains an ~19 nm circle of C-proximal polymerase domains, differentiated by strikingly diverged positions of N-proximal RNA capping/membrane binding domains. The lower ring is a "proto-crown" precursor that assembles prior to RNA template recruitment, RNA synthesis, and replication vesicle formation. In this proto-crown, the N-proximal segments interact to form a toroidal central floor, whose 3.1 Å resolution structure reveals many mechanistic details of the RNA capping/membrane binding domains. In the upper ring, cryo-EM fitting indicates that the N-proximal domains extend radially outside the polymerases, forming separated, membrane-binding "legs." The polymerase and N-proximal domains are connected by a long linker accommodating the conformational switch between the two rings and possibly also polymerase movements associated with RNA synthesis and nonsymmetric electron density in the lower center of mature crowns. The results reveal remarkable viral protein multifunctionality, conformational flexibility, and evolutionary plasticity and insights into (+)RNA virus replication and control.

PubMed: 36693094
DOI: 10.1073/pnas.2217412120

実験手法

ELECTRON MICROSCOPY (3.1 Å)