TABLE 1.
Predicted proteins expressed from WBV genomic and subgenomic RNAsa
| ORF | Nucleotides in the genome | Predicted protein size (amino acid residues) | mRNA predicted to be used for expression | Protein name |
|---|---|---|---|---|
| 1a | 906-14573 | 4,555 | 1 (genome) | Polyprotein 1a |
| 1b | 14498-21523 | 6,872 | 1 (genome) | Polyprotein 1abb |
| 2 | 21525-25187 | 1,220 | 2 | Spike protein |
| 3 | 25214-25897 | 227 | 3 | Membrane protein |
| 4 | 25915-26400 | 161 | 4 | Nucleocapsid protein |
a
By analogy with other nidoviruses, the ORF1b sequence is predicted to be expressed by (−1) ribosomal frameshifting, occurring just upstream of the ORF1a translation stop codon. Accordingly, polyprotein 1ab is encoded by two ORFs, 1a and 1b, and shares its N-terminal part with the ORF1a-encoded pp1a.
b
Note that ORF1b encodes only the C-terminal third of this protein, whereas its N-terminal two-thirds are encoded by ORF1a.