5FMZ: Crystal Structure Of Influenza B Polymerase With Bound 5' Vrna

Influenza virus polymerase transcribes or replicates the segmented RNA genome (vRNA) into respectively viral mRNA or full-length copies and initiates RNA synthesis by binding the conserved 3' and 5' vRNA ends (the promoter). In recent structures of promoter-bound polymerase, the cap-binding and endonuclease domains are configured for cap snatching, which generates capped transcription primers. Here, we present a FluB polymerase structure with a bound complementary cRNA 5' end that exhibits a major rearrangement of the subdomains within the C-terminal two-thirds of PB2 (PB2-C). Notably, the PB2 nuclear localization signal (NLS)-containing domain translocates approximately 90 A to bind to the endonuclease domain. FluA PB2-C alone and RNA-free FluC polymerase are similarly arranged. Biophysical and cap-dependent endonuclease assays show that in solution the polymerase explores different conformational distributions depending on which RNA is bound. The inherent flexibility of the polymerase allows it to adopt alternative conformations that are likely important during polymerase maturation into active progeny RNPs.
PDB ID: 5FMZDownload
MMDB ID: 135569
PDB Deposition Date: 2015/11/10
Updated in MMDB: 2016/01
Experimental Method:
x-ray diffraction
Resolution: 3.4  Å
Source Organism:
Similar Structures:
Biological Unit for 5FMZ: tetrameric; determined by author and by software (PISA)
Molecular Components in 5FMZ
Label Count Molecule
Proteins (3 molecules)
Polymerase Acidic Protein
Molecule annotation
Polymerase Basic Protein 2
Molecule annotation
RNA-directed RNA Polymerase Catalytic Subunit
Molecule annotation
Nucleotide(1 molecule)
Molecule annotation
* Click molecule labels to explore molecular sequence information.

Citing MMDB