Feline leukemia virus envelope glycoprotein (FeLV Env)

The Feline leukemia virus (FeLV) envelope glycoprotein is a critical viral surface protein responsible for mediating the entry of the retrovirus into host feline cells (UniProt: P03395). It is synthesized as a precursor (gp85) that is subsequently cleaved by host proteases into two subunits: the surface glycoprotein (gp70) and the transmembrane protein (p15E) (PubMed: PMID 10666357). The gp70 subunit facilitates binding to specific cellular receptors, such as the thiamine transporter THTR1 or the phosphate transporter Pit1, while p15E mediates the fusion of the viral and host cell membranes. Beyond its role in entry, the p15E subunit contains a highly conserved "immunosuppressive domain" that can inhibit host immune responses, contributing to the pathogenesis of FeLV-associated diseases like lymphoma, anemia, and immunodeficiency (PubMed: PMID 15564269). As the primary target for neutralizing antibodies, the envelope glycoprotein is the central component of most FeLV vaccines, such as Nobivac FeLV and Purevax FeLV, and remains a focus for developing novel antiviral therapies and monoclonal antibodies (Merck Veterinary Manual).

Other names

gp70p15Egp85 precursorSurface glycoproteinTransmembrane proteinEnv protein

Neutralization of viral entry by blocking gp70-receptor interaction and inducing protective immune responses (Merck Veterinary Manual).