title: Differential functional phenotypes of two primary HIV-1 strains resulting from homologous point mutations in the LLP domains of the envelope gp41 intracytoplasmic domain.
abstract: We previously reported that selected mutations of highly conserved arginine residues within the LLP regions of HIV-1(ME46) gp41 had diverse effects on Env function. In the current study, we sought to test if the observed LLP mutant phenotypes would be similar in HIV-1(89.6). The results of the current studies revealed that the LLP-1 mutations conferred reduced Env incorporation, infectivity, and replication phenotypes in both viruses, while homologous LLP-2 mutations had differential phenotypical effects between the two strains. In particular, several of the 89.6 LLP-2 mutant viruses were replication defective in CEMX174 cells despite having increased levels of Env incorporation, and with both strains, there were differential effects on infectivity. This comparison of homologous point mutations in two different strains of HIV supports the role of LLPs as determinants of Env function, but reveals for the first time the influence of virus strain on LLP mutant phenotypes.
authors.affiliation: Department of Molecular Genetics and Biochemistry, School of Medicine, University of Pittsburgh, PA 15261, USA.
authors.forename: Jason T
authors.initials: JT
authors.lastname: Newman
authors.forename: Timothy J
authors.initials: TJ
authors.lastname: Sturgeon
authors.forename: Phalguni
authors.initials: P
authors.lastname: Gupta
authors.forename: Ronald C
authors.initials: RC
authors.lastname: Montelaro
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002459:Cell Fusion; D015967:Gene Expression Regulation, Viral; D015686:Gene Products, env / Q000235:genetics / Q000378:metabolism; D015700:HIV Envelope Protein gp41 / Q000737:chemistry / Q000235:genetics*; D015497:HIV-1 / Q000145:classification / Q000235:genetics / Q000378:metabolism* / Q000472:pathogenicity*; D006801:Humans; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000737:chemistry / Q000235:genetics*; D010641:Phenotype; D017354:Point Mutation; D014779:Virus Replication
chemical_list: D015686:Gene Products, env; D015700:HIV Envelope Protein gp41; D010446:Peptide Fragments; C116049:lentiviral lytic peptide type 1, Human immunodeficiency virus 1