title: Analysis of human immunodeficiency virus matrix domain replacements.
abstract: The matrix (MA) domain of the HIV-1 structural precursor Gag (PrGag) protein targets PrGag proteins to membrane assembly sites, and facilitates incorporation of envelope proteins into virions. To evaluate the specific requirements for the MA membrane-binding domain (MBD) in HIV-1 assembly and replication, we examined viruses in which MA was replaced by alternative MBDs. Results demonstrated that the pleckstrin homology domains of AKT protein kinase and phospholipase C delta1 efficiently directed the assembly and release of virus-like particles (VLPs) from cells expressing chimeric proteins. VLP assembly and release also were mediated in a phorbol ester-dependent fashion by the cysteine-rich binding domain of phosphokinase Cgamma. Although alternative MBDs promoted VLP assembly and release, the viruses were not infectious. Notably, PrGag processing was reduced, while cleavage of GagPol precursors resulted in the accumulation of Pol-derived intermediates within virions. Our results indicate that the HIV-1 assembly machinery is flexible with regard to its means of membrane association, but that alternative MBDs can interfere with the elaboration of infectious virus cores.
authors.affiliation: Department of Molecular Microbiology and Immunology, Oregon Health & Sciences University, Portland, OR, USA.
authors.forename: Isabel
authors.initials: I
authors.lastname: Scholz
authors.forename: Amelia
authors.initials: A
authors.lastname: Still
authors.forename: Tenzin Choesang
authors.initials: TC
authors.lastname: Dhenub
authors.forename: Kelsey
authors.initials: K
authors.lastname: Coday
authors.forename: Mike
authors.initials: M
authors.lastname: Webb
authors.forename: Eric
authors.initials: E
authors.lastname: Barklis
mesh_terms: D001665:Binding Sites; D002460:Cell Line; D002462:Cell Membrane / Q000378:metabolism* / Q000821:virology; D004279:DNA, Viral / Q000235:genetics; D015683:Gene Products, gag / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D015497:HIV-1 / Q000235:genetics / Q000378:metabolism / Q000472:pathogenicity / Q000648:ultrastructure; D006801:Humans; D008854:Microscopy, Electron; D011498:Protein Precursors / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D017384:Sequence Deletion; D014763:Viral Matrix Proteins / Q000378:metabolism*; D014771:Virion / Q000502:physiology / Q000648:ultrastructure; D019065:Virus Assembly / Q000502:physiology*
chemical_list: D004279:DNA, Viral; D015683:Gene Products, gag; D011498:Protein Precursors; D014763:Viral Matrix Proteins