Navid Madani

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Glutamate transporters from the central nervous system play a crucial role in the clearance of the transmitter from the synaptic cleft. Glutamate is cotransported with sodium ions, and the electrogenic translocation cycle is completed by countertransport of potassium. Mutants that cannot interact with potassium are only capable of catalyzing electroneutral(More)
The vif gene of human immunodeficiency virus type 1 (HIV-1) encodes a basic Mr 23,000 protein that is necessary for production of infectious virions by nonpermissive cells (human lymphocytes and macrophages) but not by permissive cells such as HeLa-CD4. It had been proposed that permissive cells may contain an unidentified factor that functions like the(More)
When interacting with the CD4 receptor, the HIV gp120 envelope glycoprotein undergoes conformational changes that allow binding to the chemokine receptor. Receptor binding is proposed to lead to conformational changes in the gp41 transmembrane envelope glycoprotein involving the creation and/or exposure of a coiled coil consisting of three heptad repeat(More)
Binding to the CD4 receptor induces conformational changes in the human immunodeficiency virus (HIV-1) gp120 exterior envelope glycoprotein. These changes allow gp120 to bind the coreceptor, either CCR5 or CXCR4, and prime the gp41 transmembrane envelope glycoprotein to mediate virus-cell membrane fusion and virus entry. Soluble forms of CD4 (sCD4) and(More)
Human immunodeficiency virus (HIV-1) enters cells following sequential activation of the high-potential-energy viral envelope glycoprotein trimer by target cell CD4 and coreceptor. HIV-1 variants differ in their requirements for CD4; viruses that can infect coreceptor-expressing cells that lack CD4 have been generated in the laboratory. These(More)
BMS-806 and the related compound, #155, are novel inhibitors of human immunodeficiency virus type 1 (HIV-1) entry that bind the gp120 exterior envelope glycoprotein. BMS-806 and #155 block conformational changes in the HIV-1 envelope glycoproteins that are induced by binding to the host cell receptor, CD4. We tested a panel of HIV-1 envelope glycoprotein(More)
Signal transductions by the dual-function CXCR4 and CCR5 chemokine receptors/HIV type 1 (HIV-1) coreceptors were electrophysiologically monitored in Xenopus laevis oocytes that also coexpressed the viral receptor CD4 and a G protein-coupled inward-rectifying K+ channel (Kir 3.1). Large Kir 3.1-dependent currents generated in response to the corresponding(More)
Like the CCR5 chemokine receptors of humans and rhesus macaques, the very homologous (approximately 98-99% identical) CCR5 of African green monkeys (AGMs) avidly binds beta-chemokines and functions as a coreceptor for simian immunodeficiency viruses. However, AGM CCR5 is a weak coreceptor for tested macrophage-tropic (R5) isolates of human immunodeficiency(More)
The pharmacologic utility of lengthy peptides can be hindered by loss of bioactive structure and rapid proteolysis, which limits bioavailability. For example, enfuvirtide (Fuzeon, T20, DP178), a 36-amino acid peptide that inhibits human immunodeficiency virus type 1 (HIV-1) infection by effectively targeting the viral fusion apparatus, has been relegated to(More)
The viral infectivity factor (Vif) of human immunodeficiency virus type 1 (HIV-1) neutralizes an unidentified antiviral pathway that occurs only in nonpermissive (NP) cells. Using a yeast two-hybrid screen of a human lymphocyte cDNA library, we identified several potential Vif partners. One, the nuclear body protein Sp140, was found specifically in all NP(More)