6TY8

In situ structure of BmCPV RNA dependent RNA polymerase at quiescent state

Summary for 6TY8

• Entry DOI: 10.2210/pdb6ty8/pdb
• EMDB information: 20581 20582
• Descriptor: RNA-dependent RNA Polymerase, Viral structural protein 4, P1-7-METHYLGUANOSINE-P3-ADENOSINE-5',5'-TRIPHOSPHATE (3 entities in total)
• Functional Keywords: rdrp, viral protein, transferase
• Biological source: Bombyx mori cytoplasmic polyhedrosis virus (BmCPV); More
• Total number of polymer chains: 2
• Total formula weight: 203478.30

Authors

Cui, Y.X.,Zhang, Y.N.,Sun, J.C.,Zhou, Z.H. (deposition date: 2019-08-08, release date: 2019-11-20, Last modification date: 2025-06-04)

Primary citation

Cui, Y.,Zhang, Y.,Zhou, K.,Sun, J.,Zhou, Z.H.
Conservative transcription in three steps visualized in a double-stranded RNA virus.
Nat.Struct.Mol.Biol., 26:1023-1034, 2019

PubMed Abstract: Endogenous RNA transcription characterizes double-stranded RNA (dsRNA) viruses in the Reoviridae, a family that is exemplified by its simple, single-shelled member cytoplasmic polyhedrosis virus (CPV). Because of the lack of in situ structures of the intermediate stages of RNA-dependent RNA polymerase (RdRp) during transcription, it is poorly understood how RdRp detects environmental cues and internal transcriptional states to initiate and coordinate repeated cycles of transcript production inside the capsid. Here, we captured five high-resolution (2.8-3.5 Å) RdRp-RNA in situ structures-representing quiescent, initiation, early elongation, elongation and abortive states-under seven experimental conditions of CPV. We observed the 'Y'-form initial RNA fork in the initiation state and the complete transcription bubble in the elongation state. These structures reveal that de novo RNA transcription involves three major conformational changes during state transitions. Our results support an ouroboros model for endogenous conservative transcription in dsRNA viruses.

PubMed: 31695188
DOI: 10.1038/s41594-019-0320-0

Experimental method

ELECTRON MICROSCOPY (3 Å)