The late stage of human immunodeficiency virus type 1 assembly is an energy-dependent process.
Several recent studies have indicated the involvement of host cell factors in human immunodeficiency virus type 1 (HIV-1) assembly. To ascertain whether ATP-dependent factors play a role in this process, we quantified virus-like particle (VLP) production by ATP-depleted cells. Pharmacological ATP depletion abrogated VLP production without affecting cell viability or inducing degradation of HIV-1 Gag protein. This effect occurred even when the ATP-depleting agents were added 1 h into the assembly process, and it was reversed by removal of these agents. ATP depletion did not affect Gag membrane binding or multimerization. Density gradient analysis indicated that HIV-1 assembly intermediates were stalled late in the assembly process. This conclusion was further supported by electron microscopy analysis, which revealed a preponderance of plasma membrane-associated stalk-like structures in the ATP-depleted cells. Since no HIV-1 proteins bind or hydrolyze ATP, these findings indicate that an ATP-requiring cellular factor is an obligatory participant late in the HIV-1 assembly process.
Tritel
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Cell Biology Program, Memorial Sloan-Kettering Cancer Center, and Graduate Program in Cell Biology and Genetics, Weill Graduate School of Medical Sciences of Cornell University, New York, New York 10021, USA.
Resh
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MD
D000255:Adenosine Triphosphate / Q000378:metabolism*; D000818:Animals; D019556:COS Cells / Q000378:metabolism; D002462:Cell Membrane / Q000378:metabolism; D002522:Chlorocebus aethiops; D015683:Gene Products, gag / Q000378:metabolism; D015497:HIV-1 / Q000235:genetics / Q000502:physiology*; D006801:Humans; D014162:Transfection; D014771:Virion / Q000502:physiology*; D019065:Virus Assembly
D015683:Gene Products, gag; D000255:Adenosine Triphosphate