29QH

Crystal structure of Parechovirus A1 RdRP in out/down conformation

Summary for 29QH

• Entry DOI: 10.2210/pdb29qh/pdb
• Descriptor: Genome polyprotein, POTASSIUM ION (3 entities in total)
• Functional Keywords: rna-directed rna polymerase, rna replication, vpg di-uridylylation, viral protein
• Biological source: Parechovirus ahumpari
• Total number of polymer chains: 1
• Total formula weight: 53779.22

Authors

Guryanov, S.G.,Kajander, T.,Mitchell, C.,Butcher, S.J. (deposition date: 2026-03-30, release date: 2026-09-23)

Primary citation

Guryanov, S.G.,Mitchell, C.,Kajander, T.,Butcher, S.J.
Crystal structures of Parechovirus A1 3D pol reveal a mechanism of conformational stabilization in +ssRNA virus RNA-dependent RNA polymerase.
J.Struct.Biol., 218:108370-108370, 2026

PubMed Abstract: Parechovirus A1 (PeV A1) 3D is an RNA-dependent RNA polymerase responsible for replication of the virus genome. We solved crystal structures of PeV A1 3D structure in complex with GTP and in apo-state at 1.8-2.0 Å resolutions. In the 3D-GTP complex, the conformation of the conserved motif B loop was stabilized by zinc ion coordination by cysteine residues. Apo-state structures of PeV A1 3D showed significant conformational flexibility in the motif B loop, in the absence of zinc. While one of the conformational states of apo-3D was similar to the 3D-GTP complex structure, the alternative apo-3D conformation showed a 4.3 Å movement of the motif B loop out of the active site cavity relative to the complex of 3D with GTP. We propose that PeV A1 3D activity is regulated by conformational stabilization of the motif B loop by zinc coordination.

PubMed: 42722143
DOI: 10.1016/j.jsb.2026.108370

Experimental method

X-RAY DIFFRACTION (2 Å)