7Z2J
White Bream virus N7-Methyltransferase
Summary for 7Z2J
| Entry DOI | 10.2210/pdb7z2j/pdb |
| Related | 7Z05 |
| Descriptor | Non-structural protein 1, S-ADENOSYL-L-HOMOCYSTEINE (3 entities in total) |
| Functional Keywords | n7-methyl transferase, capping enzyme, transferase |
| Biological source | White bream virus |
| Total number of polymer chains | 1 |
| Total formula weight | 29714.60 |
| Authors | Shannon, A.,Gauffre, P.,Canard, B.,Ferron, F. (deposition date: 2022-02-28, release date: 2022-11-02, Last modification date: 2024-01-31) |
| Primary citation | Shannon, A.,Sama, B.,Gauffre, P.,Guez, T.,Debart, F.,Vasseur, J.J.,Decroly, E.,Canard, B.,Ferron, F. A second type of N7-guanine RNA cap methyltransferase in an unusual locus of a large RNA virus genome. Nucleic Acids Res., 50:11186-11198, 2022 Cited by PubMed Abstract: The order Nidovirales is a diverse group of (+)RNA viruses, with a common genome organization and conserved set of replicative and editing enzymes. In particular, RNA methyltransferases play a central role in mRNA stability and immune escape. However, their presence and distribution in different Nidovirales families is not homogeneous. In Coronaviridae, the best characterized family, two distinct methytransferases perform methylation of the N7-guanine and 2'-OH of the RNA-cap to generate a cap-1 structure (m7GpppNm). The genes of both of these enzymes are located in the ORF1b genomic region. While 2'-O-MTases can be identified for most other families based on conservation of both sequence motifs and genetic loci, identification of the N7-guanine methyltransferase has proved more challenging. Recently, we identified a putative N7-MTase domain in the ORF1a region (N7-MT-1a) of certain members of the large genome Tobaniviridae family. Here, we demonstrate that this domain indeed harbors N7-specific methyltransferase activity. We present its structure as the first N7-specific Rossmann-fold (RF) MTase identified for (+)RNA viruses, making it remarkably different from that of the known Coronaviridae ORF1b N7-MTase gene. We discuss the evolutionary implications of such an appearance in this unexpected location in the genome, which introduces a split-off in the classification of Tobaniviridae. PubMed: 36265859DOI: 10.1093/nar/gkac876 PDB entries with the same primary citation |
| Experimental method | X-RAY DIFFRACTION (1.657 Å) |
Structure validation
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