title: A single amino acid substitution within the transmembrane domain of the human immunodeficiency virus type 1 Vpu protein renders simian-human immunodeficiency virus (SHIV(KU-1bMC33)) susceptible to rimantadine.
abstract: Previous studies from our laboratory have shown that the transmembrane domain (TM) of the Vpu protein of human immunodeficiency virus type 1 (HIV-1) contributes to the pathogenesis of SHIV(KU-1bMC33) in macaques and that the TM domain of Vpu could be replaced with the M2 protein viroporin from influenza A virus. Recently, we showed that the replacement of the TM domain of Vpu with that of the M2 protein of influenza A virus resulted in a virus (SHIV(M2)) that was sensitive to rimantadine [Hout, D.R., Gomez, M.L., Pacyniak, E., Gomez, L.M., Inbody, S.H., Mulcahy, E.R., Culley, N., Pinson, D.M., Powers, M.F., Wong, S.W., Stephens, E.B., 2006. Substitution of the transmembrane domain of Vpu in simian human immunodeficiency virus (SHIV(KU-1bMC33)) with that of M2 of influenza A results in a virus that is sensitive to inhibitors of the M2 ion channel and is pathogenic for pig-tailed macaques. Virology 344, 541-558]. Based on previous studies of the M2 protein which have shown that the His-X-X-X-Trp motif within the M2 is essential to the function of the M2 proton channel, we have constructed a novel SHIV in which the alanine at position 19 of the TM domain was replaced with a histidine residue resulting in the motif His-Ile-Leu-Val-Trp. The SHIV(VpuA19H) replicated with similar kinetics as the parental SHIV(KU-1bMC33) and pulse-chase analysis revealed that the processing of viral proteins was similar to SHIV(KU-1bMC33). This SHIV(VpuA19H) virus was found to be more sensitive to the M2 ion channel blocker rimantadine than SHIV(M2). Electron microscopic examination of SHIV(VpuA19H)-infected cells treated with rimantadine revealed an accumulation of viral particles at the cell surface and within intracellular vesicles, which was similar to that previously observed to SHIV(M2)-infected cells treated with rimantadine. These data indicate that the Vpu protein of HIV-1 can be converted into a rimantadine-sensitive ion channel with the alteration of one amino acid and provide additional evidence that drugs targeting the Vpu TM/ion channel can be effective anti-HIV-1 drugs.
authors.affiliation: Department of Anatomy and Cell Biology, University of Kansas Medical Center, Kansas City, 66160, USA.
authors.forename: David R
authors.initials: DR
authors.lastname: Hout
authors.forename: Lisa M
authors.initials: LM
authors.lastname: Gomez
authors.forename: Erik
authors.initials: E
authors.lastname: Pacyniak
authors.forename: Jean-Marie
authors.initials: JM
authors.lastname: Miller
authors.forename: M Sarah
authors.initials: MS
authors.lastname: Hill
authors.forename: Edward B
authors.initials: EB
authors.lastname: Stephens
mesh_terms: D000595:Amino Acid Sequence; D019943:Amino Acid Substitution; D000818:Animals; D019380:Anti-HIV Agents / Q000494:pharmacology*; D001483:Base Sequence; D001693:Biological Transport, Active; D015704:CD4 Antigens / Q000378:metabolism; D004279:DNA, Viral / Q000235:genetics; D024882:Drug Resistance, Viral / Q000235:genetics; D016338:Genes, vpu; D015497:HIV-1 / Q000737:chemistry / Q000187:drug effects* / Q000235:genetics*; D006367:HeLa Cells; D054298:Human Immunodeficiency Virus Proteins; D006801:Humans; D006824:Hybridization, Genetic; D007473:Ion Channels / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D008854:Microscopy, Electron; D008969:Molecular Sequence Data; D017434:Protein Structure, Tertiary; D012299:Rimantadine / Q000494:pharmacology*; D015302:Simian Immunodeficiency Virus / Q000737:chemistry / Q000187:drug effects* / Q000235:genetics*; D014763:Viral Matrix Proteins / Q000737:chemistry / Q000235:genetics; D054334:Viral Regulatory and Accessory Proteins / Q000737:chemistry* / Q000235:genetics* / Q000378:metabolism; D000086082:Viroporin Proteins
chemical_list: D019380:Anti-HIV Agents; D015704:CD4 Antigens; D004279:DNA, Viral; D054298:Human Immunodeficiency Virus Proteins; D007473:Ion Channels; D012299:Rimantadine; D014763:Viral Matrix Proteins; D054334:Viral Regulatory and Accessory Proteins; C488937:M2 protein, Influenza A virus; D000086082:Viroporin Proteins; C514859:vpu protein, Human immunodeficiency virus 1