title: Maturation of the HIV-1 core by a non-diffusional phase transition.
abstract: The formation of the HIV-1 core is the final step in the viral maturation pathway, resulting in the formation of infectious virus. Most current models for HIV-1 core formation suggest that, upon proteolytic cleavage from the immature Gag, capsid (CA) dissociates into the viral interior before reforming into the core. Here we present evidence for an alternate view of core formation by taking advantage of our serendipitous observation of large membrane-enclosed structures in HIV-1 supernatants from infected cells. Cryo-electron tomographic studies show that these structures, which contain ordered arrays of what is likely the membrane-associated matrix protein, contain multiple cores that can be captured at different stages of maturation. Our studies suggest that HIV maturation involves a non-diffusional phase transition in which the detaching layer of the cleaved CA lattice is gradually converted into a roll that ultimately forms the surface of the mature conical core.
authors.affiliation: Laboratory of Cell Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892, USA.
authors.forename: Gabriel A
authors.initials: GA
authors.lastname: Frank
authors.affiliation: Laboratory of Cell Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892, USA.
authors.forename: Kedar
authors.initials: K
authors.lastname: Narayan
authors.affiliation: AIDS and Cancer Virus Program, Leidos Biomedical Research, Inc., Frederick National Laboratory, Frederick, Maryland 21702, USA.
authors.forename: Julian W
authors.initials: JW
authors.lastname: Bess
authors.affiliation: AIDS and Cancer Virus Program, Leidos Biomedical Research, Inc., Frederick National Laboratory, Frederick, Maryland 21702, USA.
authors.forename: Gregory Q
authors.initials: GQ
authors.lastname: Del Prete
authors.affiliation: Laboratory of Computational Biology, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland 20892, USA.
authors.forename: Xiongwu
authors.initials: X
authors.lastname: Wu
authors.affiliation: National Laboratory of Medicine, National Institutes of Health, Bethesda, Maryland 20892, USA.
authors.forename: Amy
authors.initials: A
authors.lastname: Moran
authors.affiliation: Laboratory of Cell Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892, USA.
authors.forename: Lisa M
authors.initials: LM
authors.lastname: Hartnell
authors.affiliation: Laboratory of Cell Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892, USA.
authors.forename: Lesley A
authors.initials: LA
authors.lastname: Earl
authors.affiliation: AIDS and Cancer Virus Program, Leidos Biomedical Research, Inc., Frederick National Laboratory, Frederick, Maryland 21702, USA.
authors.forename: Jeffrey D
authors.initials: JD
authors.lastname: Lifson
authors.affiliation: Laboratory of Cell Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892, USA.
authors.forename: Sriram
authors.initials: S
authors.lastname: Subramaniam
mesh_terms: D002213:Capsid / Q000502:physiology; D002460:Cell Line; D002499:Centrifugation, Density Gradient; D020285:Cryoelectron Microscopy; D015497:HIV-1 / Q000502:physiology*; D006801:Humans; D046529:Microscopy, Electron, Transmission; D008954:Models, Biological; D019065:Virus Assembly / Q000502:physiology*; D054301:gag Gene Products, Human Immunodeficiency Virus / Q000378:metabolism
chemical_list: D054301:gag Gene Products, Human Immunodeficiency Virus