4UCL: X-ray Structure And Activities Of An Essential Mononegavirales L-protein Domain

The L protein of mononegaviruses harbours all catalytic activities for genome replication and transcription. It contains six conserved domains (CR-I to -VI; Fig. 1a). CR-III has been linked to polymerase and polyadenylation activity, CR-V to mRNA capping and CR-VI to cap methylation. However, how these activities are choreographed is poorly understood. Here we present the 2.2-A X-ray structure and activities of CR-VI+, a portion of human Metapneumovirus L consisting of CR-VI and the poorly conserved region at its C terminus, the +domain. The CR-VI domain has a methyltransferase fold, which besides the typical S-adenosylmethionine-binding site ((SAM)P) also contains a novel pocket ((NS)P) that can accommodate a nucleoside. CR-VI lacks an obvious cap-binding site, and the (SAM)P-adjoining site holding the nucleotides undergoing methylation ((SUB)P) is unusually narrow because of the overhanging +domain. CR-VI+ sequentially methylates caps at their 2'O and N7 positions, and also displays nucleotide triphosphatase activity.
PDB ID: 4UCLDownload
MMDB ID: 134217
PDB Deposition Date: 2014/12/3
Updated in MMDB: 2015/11
Experimental Method:
x-ray diffraction
Resolution: 2.8  Å
Similar Structures:
Biological Unit for 4UCL: monomeric; determined by author and by software (PISA)
Molecular Components in 4UCL
Label Count Molecule
Protein (1 molecule)
RNA-directed RNA Polymerase L
Molecule annotation
Chemicals (2 molecules)
* Click molecule labels to explore molecular sequence information.

Citing MMDB