Synthesis, oligomerization, and biological activity of the human immunodeficiency virus type 2 envelope glycoprotein expressed by a recombinant vaccinia virus.
The full-length envelope gene from an infectious human immunodeficiency virus type 2 (HIV-2) molecular clone was expressed in CD4+ and CD4- cells by a recombinant vaccinia virus vector. Pulse-chase experiments indicated that gp160 was processed into gp120 and gp41 subunits. Although large amounts of gp120 were shed into the medium, the recombinant vaccinia virus-infected cells fused with uninfected CD4+ cells. The receptor binding of HIV-2 gp120 was further analyzed using a panel composed of nine soluble CD4 mutants containing insertions of 2 amino acids within the first and second immunoglobulin-like domains. Of three mutations previously shown to interfere with HIV-1 gp120 binding, two also interfered with binding of the HIV-2 glycoprotein indicating use of the same binding site. Chemical crosslinking, sucrose gradient sedimentation, and sodium dodecyl sulfate-polyacrylamide gel electrophoresis were employed to study the oligomerization of the envelope protein. The data indicated that gp160 assembles posttranslationally into dimers and higher oligomers that are probably tetramers.
Chakrabarti
S
S
Laboratory of Viral Diseases, National Institute of Allergy and Infectious Diseases, Bethesda, MD 20892.
Mizukami
T
T
Franchini
G
G
Moss
B
B
D000818:Animals; D015704:CD4 Antigens / Q000235:genetics / Q000276:immunology; D003001:Cloning, Molecular; D003432:Cross-Linking Reagents / Q000378:metabolism; D003588:Cytopathogenic Effect, Viral; D015699:HIV Envelope Protein gp120 / Q000235:genetics / Q000276:immunology*; D015700:HIV Envelope Protein gp41 / Q000235:genetics / Q000276:immunology; D015498:HIV-2 / Q000235:genetics / Q000378:metabolism; D000882:Haplorhini; D006801:Humans; D009154:Mutation; D011499:Protein Processing, Post-Translational; D011991:Receptors, Virus / Q000276:immunology; D012995:Solubility; D014616:Vaccinia virus / Q000235:genetics*
D015704:CD4 Antigens; D003432:Cross-Linking Reagents; D015699:HIV Envelope Protein gp120; D015700:HIV Envelope Protein gp41; D011991:Receptors, Virus