A sequence similar to tRNA 3 Lys gene is embedded in HIV-1 U3-R and promotes minus-strand transfer

Nat Struct Mol Biol. 2010 Jan;17(1):83-9. doi: 10.1038/nsmb.1687. Epub 2009 Dec 6.

Abstract

We identified a sequence embedded in the U3-R region of HIV-1 RNA that is highly complementary to human tRNA(3)(Lys). The free energy of annealing to tRNA(3)(Lys) is significantly lower for this sequence and the primer-binding site than for other viral sequences of similar length. The only interruption in complementarity is a 29-nucleotide segment inserted where a tRNA intron would be expected. The insert contains the TATA box for viral RNA transcription. The embedded sequence includes a 9-nucleotide segment previously reported to aid minus-strand transfer by binding the primer tRNA(3)(Lys). Reconstituting transfer in vitro, we show that including segments from the embedded sequence in the acceptor template, beyond the 9 nucleotides, further increases transfer efficiency. We propose that a gene encoding tRNA(3)(Lys) was incorporated during HIV-1 evolution and retained, largely intact, because of its roles in transcription and strand transfer.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Base Sequence
  • Computational Biology
  • Conserved Sequence / genetics
  • Evolution, Molecular*
  • HIV-1 / genetics*
  • Humans
  • Molecular Sequence Data
  • Oligonucleotides / genetics
  • RNA, Transfer, Lys / genetics*
  • RNA, Viral / genetics*
  • Sequence Alignment
  • Transcription, Genetic / genetics*

Substances

  • Oligonucleotides
  • RNA, Transfer, Lys
  • RNA, Viral