A novel interaction of tRNA(Lys,3) with the feline immunodeficiency virus RNA genome governs initiation of minus strand DNA synthesis

J Biol Chem. 2001 Jul 20;276(29):27721-30. doi: 10.1074/jbc.M100513200. Epub 2001 May 15.

Abstract

Complementarity between nucleotides at the 5' terminus of tRNA(Lys,3) and the U5-IR loop of the feline immunodeficiency virus RNA genome suggests a novel intermolecular interaction controls initiation of minus strand synthesis in a manner analogous to other retroviral systems. Base pairing of this tRNA-viral RNA duplex was confirmed by nuclease mapping of the RNA genome containing full-length or 5'-deleted variants of tRNA(Lys,3) hybridized to the primer-binding site. A major pause in RNA-dependent DNA synthesis occurred 14 nucleotides ahead of the primer-binding site with natural and synthetic tRNA(Lys,3) primers, indicating it was not a consequence of tRNA base modifications. The majority of the paused complexes resulted in dissociation of the reverse transcriptase from the template/primer, as demonstrated by an assay limited to a single binding event. Hybridization of a tRNA mutant whose 5' nucleotides are deleted relieved pausing at this position and subsequently allowed high level DNA synthesis. Additional experiments with tRNA-DNA chimeric primers were used to localize the stage of minus strand synthesis at which the tRNA-viral RNA interaction was disrupted. Finally, replacing nucleotides of the feline immunodeficiency virus U5-IR loop with the (A)(4) sequence of its human immunodeficiency virus (HIV)-1 counterpart also relieved pausing, but did not induce pausing immediately downstream of the primer-binding site previously noted during initiation of HIV-1 DNA synthesis. These combined observations provide further evidence of cis-acting sequences immediately adjacent to the primer-binding site controlling initiation of minus strand DNA synthesis in retroviruses and retrotransposons.

MeSH terms

  • Base Sequence
  • DNA Replication / genetics*
  • Genome, Viral*
  • Immunodeficiency Virus, Feline / genetics*
  • Nucleic Acid Conformation
  • RNA, Transfer, Lys / chemistry
  • RNA, Transfer, Lys / metabolism*
  • RNA, Viral / chemistry
  • RNA, Viral / metabolism*

Substances

  • RNA, Transfer, Lys
  • RNA, Viral