Host cell proteins bind specifically to the capsid-cleaved 5' end of Leishmaniavirus RNA

J Biochem. 1999 Sep;126(3):538-44. doi: 10.1093/oxfordjournals.jbchem.a022483.

Abstract

Leishmaniavirus (LRV) is a double-stranded RNA (dsRNA) virus that persistently infects some strains of the protozoan parasite, Leishmania. LRV generates a short transcript, corresponding to the 5' end of the positive-sense RNA (320 nt), via a cleavage event mediated by the viral capsid protein on the full-length positive sense RNA transcript. To address the possibility that the RNA cleavage represents a regulatory mechanism for maintaining persistent infection, the interactions between Leishmania cytoplasmic proteins and in vitro synthesized viral transcripts were studied. In gel mobility shift experiments, three specific RNA/protein complexes were formed between cellular proteins and the cleaved viral transcript, and three major proteins were labeled by UV cross-linking. No protein binding activity was observed for either the short (320 nt) or full-length RNA transcripts. However, the two cleavage reaction products were able to form stable RNA/RNA complexes. We present a model in which the virus is targeting its own transcript for cleavage to promote binding of host factors to cryptic domains inaccessible in the full-length transcript.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • 5' Untranslated Regions
  • Binding Sites
  • Capsid*
  • Cell Line
  • Leishmaniavirus / genetics*
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism*
  • RNA, Viral / genetics
  • RNA, Viral / metabolism*
  • RNA-Binding Proteins / metabolism*

Substances

  • 5' Untranslated Regions
  • RNA, Messenger
  • RNA, Viral
  • RNA-Binding Proteins