The p10 gene of natural isolates of Bombyx mori nuclear polyhedrosis virus encodes a truncated protein with an M(r) of 7700.

Sequence analysis of the p10 genes of three Bombyx mori nuclear polyhedrosis virus (BmNPV) isolates collected in Taiwan (Ta) and Japan (T3 and D1) showed that all possessed a deletion of an adenine residue, 210 bp downstream from the first base of the initiation codon when compared to the p10 gene of Autographa californica (multinucleocapsid) NPV (AcMNPV). This deletion caused a downstream termination codon to come inframe with the coding sequence of p10, so that the p10 gene of BmNPV encoded a protein of 70 amino acid residues with an M(r) of 7700. This is considerably shorter than the 10,000 M(r) protein encoded by the closely related AcMNPV.