ALIX is recruited temporarily into HIV-1 budding sites at the end of gag assembly.
Polymerization of Gag on the inner leaflet of the plasma membrane drives the assembly of Human Immunodeficiency Virus 1 (HIV-1). Gag recruits components of the endosomal sorting complexes required for transport (ESCRT) to facilitate membrane fission and virion release. ESCRT assembly is initiated by recruitment of ALIX and TSG101/ESCRT-I, which bind directly to the viral Gag protein and then recruit the downstream ESCRT-III and VPS4 factors to complete the budding process. In contrast to previous models, we show that ALIX is recruited transiently at the end of Gag assembly, and that most ALIX molecules are recycled into the cytosol as the virus buds, although a subset remains within the virion. Our experiments imply that ALIX is recruited to the neck of the assembling virion and is mostly recycled after virion release.
Department of Physics and Astronomy, University of Utah, Salt Lake City, Utah, United States of America.
Pei-I
PI
Ku
Department of Physics and Astronomy, University of Utah, Salt Lake City, Utah, United States of America.
Mourad
M
Bendjennat
Department of Physics and Astronomy, University of Utah, Salt Lake City, Utah, United States of America.
Jeff
J
Ballew
Department of Physics and Astronomy, University of Utah, Salt Lake City, Utah, United States of America.
Michael B
MB
Landesman
Department of Physics and Astronomy, University of Utah, Salt Lake City, Utah, United States of America; Center for Cell and Genome Science, University of Utah, Salt Lake City, Utah, United States of America; Department of Biology, University of Utah, Salt Lake City, Utah, United States of America.
Saveez
S
Saffarian
D000074183:ATPases Associated with Diverse Cellular Activities; D002135:Calcium-Binding Proteins / Q000378:metabolism*; D018797:Cell Cycle Proteins / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000378:metabolism / Q000502:physiology*; D056827:Endosomal Sorting Complexes Required for Transport / Q000378:metabolism* / Q000502:physiology*; D057809:HEK293 Cells; D015497:HIV-1 / Q000502:physiology*; D006367:HeLa Cells; D006801:Humans; D018613:Microscopy, Confocal; D014157:Transcription Factors / Q000378:metabolism / Q000502:physiology*; D025262:Vacuolar Proton-Translocating ATPases / Q000378:metabolism; D019065:Virus Assembly / Q000502:physiology*; D054301:gag Gene Products, Human Immunodeficiency Virus / Q000378:metabolism*; D000099177:Tsg101 Protein
D000074183:ATPases Associated with Diverse Cellular Activities; D002135:Calcium-Binding Proteins; D018797:Cell Cycle Proteins; D004268:DNA-Binding Proteins; D056827:Endosomal Sorting Complexes Required for Transport; D014157:Transcription Factors; D025262:Vacuolar Proton-Translocating ATPases; D054301:gag Gene Products, Human Immunodeficiency Virus; D000099177:Tsg101 Protein; C117020:PDCD6IP protein, human; C490305:VPS4A protein, human