FIG. 1.
MHV genome organization. The diagram shows the organization of the 22-kb MHV-A59 gene 1 (replicase gene) and the locations of genes 6 and 7, encoding the structural proteins M and N, respectively. Gene 1 is composed of two open reading frames (ORF1a and ORF1b). The ORF1a-ORF1b fusion replicase polyprotein is shown, with mature replicase proteins represented as boxes. Proteins with confirmed or predicted functions include two papain-like proteinases (PLP1 and PLP2), the 3C-like proteinase (3CLpro), two transmembrane proteins (MP1 and MP2), the RNA-dependent RNA polymerase (Pol), and the RNA helicase (Hel). All other proteins are labeled based on their molecular masses in kilodaltons. The gray boxes represent replicase proteins of interest in the present study: the amino-terminal cleavage product, p28, and two carboxy-terminal ORF1a proteins, p10 and p15. The region of the gene 1 polyprotein (amino acids M1 to G247) used to generate α-p28 guinea pig (GP3) and rabbit (VU221) polyclonal antisera is indicated.