HUMAN-IMMUNODEFICIENCY-VIRUS TYPE-1 AND TYPE-2 ENVELOPE GLYCOPROTEINSOLIGOMERIZE THROUGH CONSERVED SEQUENCES

Hetero-oligomerization between human immunodeficiency virus type 2 (HI V-2) envelope glycoprotein (Env) truncation mutants and epitope-tagged gp160 is dependent on the presence of gp41 transmembrane protein (TMI amino acids 552 to 589, a putative amphipathic alpha-helical sequence . HIV-2 Env truncation mutants containing this sequence were also able to form cross-type hetero-oligomers with HIV-1 Env, HIV-2/HIV-1 heter o-oligomerization was, however, more sensitive to disruption by mutage nesis or increased temperature. The conservation of the Env oligomeriz ation function of the HIV-1 and HIV-2 alpha-helical sequences suggests that retroviral TM alpha-helical motifs may have a universal role in oligomerization.