title: A leucine triplet repeat sequence (LXX)4 in p6gag is important for Vpr incorporation into human immunodeficiency virus type 1 particles.
abstract: Incorporation of Vpr into human immunodeficiency virus type 1 (HIV-1) virions is mediated by the Gag protein, independently of other viral components. We have coexpressed Vpr and Gag constructs in a vaccinia virus expression system in order to map the region of Gag involved in Vpr packaging. Deletion of the carboxyl-terminal p6 region of Gag impaired the ability of Gag to package Vpr. To confirm the role of p6 in Vpr packaging, Rous sarcoma virus (RSV)-HIV chimeras containing HIV-1 p6 were constructed. Although RSV Gag does not package Vpr into virus particles, a chimera containing HIV-1 p6 is sufficient for Vpr incorporation. To map the region of p6 involved in Vpr packaging, a series of p6 point mutations and deletion mutations was analyzed. Mutations in the N-terminal p6 proline-rich domain, for which preliminary evidence shows a marked decrease in virion incorporated RNA, did not affect Vpr incorporation. Deletion of residues 1 to 31 of HIV-1 p6 did not affect Vpr packaging, but residues 35 to 47, including an (LXX)4 domain, were required for Vpr incorporation into virus particles.
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002460:Cell Line; D017931:DNA Primers; D015870:Gene Expression; D015683:Gene Products, gag / Q000096:biosynthesis / Q000378:metabolism*; D016336:Gene Products, vpr / Q000096:biosynthesis / Q000378:metabolism*; D015750:Genes, gag; D015497:HIV-1 / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D007930:Leucine; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D010957:Plasmids; D016133:Polymerase Chain Reaction; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000378:metabolism; D014616:Vaccinia virus; D054325:vpr Gene Products, Human Immunodeficiency Virus
chemical_list: D017931:DNA Primers; D015683:Gene Products, gag; D016336:Gene Products, vpr; D011994:Recombinant Proteins; D054325:vpr Gene Products, Human Immunodeficiency Virus; D007930:Leucine