title: Molecular mimicry of human tRNALys anti-codon domain by HIV-1 RNA genome facilitates tRNA primer annealing.
abstract: The primer for initiating reverse transcription in human immunodeficiency virus type 1 (HIV-1) is tRNA(Lys3). Host cell tRNA(Lys) is selectively packaged into HIV-1 through a specific interaction between the major tRNA(Lys)-binding protein, human lysyl-tRNA synthetase (hLysRS), and the viral proteins Gag and GagPol. Annealing of the tRNA primer onto the complementary primer-binding site (PBS) in viral RNA is mediated by the nucleocapsid domain of Gag. The mechanism by which tRNA(Lys3) is targeted to the PBS and released from hLysRS prior to annealing is unknown. Here, we show that hLysRS specifically binds to a tRNA anti-codon-like element (TLE) in the HIV-1 genome, which mimics the anti-codon loop of tRNA(Lys) and is located proximal to the PBS. Mutation of the U-rich sequence within the TLE attenuates binding of hLysRS in vitro and reduces the amount of annealed tRNA(Lys3) in virions. Thus, LysRS binds specifically to the TLE, which is part of a larger LysRS binding domain in the viral RNA that includes elements of the Psi packaging signal. Our results suggest that HIV-1 uses molecular mimicry of the anti-codon of tRNA(Lys) to increase the efficiency of tRNA(Lys3) annealing to viral RNA.
authors.affiliation: Department of Chemistry and Biochemistry, Center for Retroviral Research, and Center for RNA Biology, The Ohio State University, Columbus, Ohio 43210, USA.
authors.forename: Christopher P
authors.initials: CP
authors.lastname: Jones
authors.forename: Jenan
authors.initials: J
authors.lastname: Saadatmand
authors.forename: Lawrence
authors.initials: L
authors.lastname: Kleiman
authors.forename: Karin
authors.initials: K
authors.lastname: Musier-Forsyth
mesh_terms: D020029:Base Pairing; D024202:Electrophoretic Mobility Shift Assay; D016679:Genome, Viral / Q000235:genetics*; D016322:HIV Enhancer / Q000235:genetics; D015497:HIV-1 / Q000235:genetics* / Q000502:physiology; D006801:Humans; D008250:Lysine-tRNA Ligase / Q000235:genetics* / Q000378:metabolism; D018716:Molecular Mimicry; D009154:Mutation; D017434:Protein Structure, Tertiary; D012313:RNA; D012357:RNA, Transfer, Lys / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D012367:RNA, Viral / Q000235:genetics* / Q000378:metabolism; D019065:Virus Assembly / Q000235:genetics; D014779:Virus Replication / Q000235:genetics; D054301:gag Gene Products, Human Immunodeficiency Virus / Q000378:metabolism*
chemical_list: C034477:RNA primers; D012357:RNA, Transfer, Lys; D012367:RNA, Viral; D054301:gag Gene Products, Human Immunodeficiency Virus; D012313:RNA; D008250:Lysine-tRNA Ligase