GP180, A HOST-CELL GLYCOPROTEIN THAT FINDS DUCK HEPATITIS-B VIRUS-PARTICLES, IS ENCODED BY A MEMBER OF THE CARBOXYPEPTIDASE GENE FAMILY

Duck hepatitis B virus particles bearing the L and S envelope proteins bind a cellular glycoprotein of 180 kDa (gp180) with high affinity an d specificity. Binding is mediated by the pre-S region of the L protei n and is blocked by neutralizing but not by non-neutralizing monoclona l antibodies to the virus. These and other properties have suggested t hat gp180 may be a component of the viral entry machinery. Here we rep ort the purification of gp180 from duck liver and the isolation and ch aracterization of cDNA encoding it. DNA sequence analysis of this cDNA indicates that gp180 is a novel member of the basic carboxypeptidase gene family.