1HI1

RNA dependent RNA polymerase from dsRNA bacteriophage phi6 plus bound NTP

Summary for 1HI1

• Entry DOI: 10.2210/pdb1hi1/pdb
• Related: 1HHS 1HHT 1HI0 1HI8
• Descriptor: P2 PROTEIN, ADENOSINE-5'-TRIPHOSPHATE (2 entities in total)
• Functional Keywords: rna polymerase, viral polymerase
• Biological source: BACTERIOPHAGE PHI-6 (PHAGE PHI 6)
• Total number of polymer chains: 3
• Total formula weight: 226231.15

Authors

Grimes, J.M.,Butcher, S.J.,Makeyev, E.V.,Bamford, D.H.,Stuart, D.I. (deposition date: 2001-01-01, release date: 2001-03-27, Last modification date: 2024-05-08)

Primary citation

Butcher, S.J.,Grimes, J.M.,Makeyev, E.V.,Bamford, D.H.,Stuart, D.I.
A Mechanism for Initiating RNA-Dependent RNA Polymerization
Nature, 410:235-, 2001

PubMed Abstract: In most RNA viruses, genome replication and transcription are catalysed by a viral RNA-dependent RNA polymerase. Double-stranded RNA viruses perform these operations in a capsid (the polymerase complex), using an enzyme that can read both single- and double-stranded RNA. Structures have been solved for such viral capsids, but they do not resolve the polymerase subunits in any detail. Here we show that the 2 A resolution X-ray structure of the active polymerase subunit from the double-stranded RNA bacteriophage straight phi6 is highly similar to that of the polymerase of hepatitis C virus, providing an evolutionary link between double-stranded RNA viruses and flaviviruses. By crystal soaking and co-crystallization, we determined a number of other structures, including complexes with oligonucleotide and/or nucleoside triphosphates (NTPs), that suggest a mechanism by which the incoming double-stranded RNA is opened up to feed the template through to the active site, while the substrates enter by another route. The template strand initially overshoots, locking into a specificity pocket, and then, in the presence of cognate NTPs, reverses to form the initiation complex; this process engages two NTPs, one of which acts with the carboxy-terminal domain of the protein to prime the reaction. Our results provide a working model for the initiation of replication and transcription.

PubMed: 11242087
DOI: 10.1038/35065653

Experimental method

X-RAY DIFFRACTION (3 Å)