THE HIGHLY O-GLYCOSYLATED GLYCOPROTEIN GP2 OF EQUINE HERPESVIRUS-1 ISENCODED BY GENE-71

There have been conflicting reports regarding the gene assignment of t he high-molecular-mass envelope glycoprotein gp2 (gp300) of equine her pesvirus 1. Here, we provide an unequivocal demonstration that gp2 is encoded by gene 71. gp2 that was purified with a defining monoclonal a ntibody was cleaved internally to yield a 42-kDa protein encoded by ge ne 71. Amino acid composition data and N-terminal sequence analysis of a tryptic peptide identified gp2 as the product of equine herpesvirus 1 gene 71 with the SWISS-PROT database. Analysis of gp2's monosacchar ide composition and the 42-kDa subunit showed that the high level of O glycosylation occurs on the serine/threonine-rich region upstream of the cleavage site.