title: HIV-1-associated PKA acts as a cofactor for genome reverse transcription.
abstract: BACKGROUND
  Host cell proteins, including cellular kinases, are embarked into intact HIV-1 particles. We have previously shown that the Cα catalytic subunit of cAMP-dependent protein kinase is packaged within HIV-1 virions as an enzymatically active form able to phosphorylate a synthetic substrate in vitro (Cartier et al. J. Biol. Chem. 278:35211 (2003)). The present study was conceived to investigate the contribution of HIV-1-associated PKA to the retroviral life cycle.
  
  
  RESULTS
  NL4.3 viruses were produced from cells cultured in the presence of PKA inhibitors H89 (H89-NL4.3) or Myr-PKI (PKI-NL4.3) and analyzed for viral replication. Despite being mature and normally assembled, and containing expected levels of genomic RNA and RT enzymatic activity, such viruses showed poor infectivity. Indeed, infection generated reduced amounts of strong-strop minus strand DNA, while incoming RNA levels in target cells were unaffected. Decreased cDNA synthesis was also evidenced in intact H89-NL4.3 and PKI-NL4.3 cell free particles using endogenous reverse transcription (ERT) experiments. Moreover, similar defects were reproduced when wild type NL4.3 particles preincubated with PKA inhibitors were subjected to ERT reactions.
  
  
  CONCLUSIONS
  Altogether, our results indicate that HIV-1-associated PKA is required for early reverse transcription of the retroviral genome both in cell free intact viruses and in target cells. Accordingly, virus-associated PKA behaves as a cofactor of an intraviral process required for optimal reverse transcription and for early post-entry events.
authors.forename: Charline
authors.initials: C
authors.lastname: Giroud
authors.forename: Nathalie
authors.initials: N
authors.lastname: Chazal
authors.forename: Bernard
authors.initials: B
authors.lastname: Gay
authors.forename: Patrick
authors.initials: P
authors.lastname: Eldin
authors.forename: Sonia
authors.initials: S
authors.lastname: Brun
authors.affiliation: Centre d'étude d'agents Pathogènes et Biotechnologies pour la Santé (CPBS)-CNRS UMR 5236, Université Montpellier 1,2, 1919 route de Mende, Montpellier, cedex 2 34293, France. laurence.briant@cpbs.cnrs.fr.
authors.forename: Laurence
authors.initials: L
authors.lastname: Briant
mesh_terms: D002460:Cell Line; D017868:Cyclic AMP-Dependent Protein Kinases / Q000378:metabolism*; D015497:HIV-1 / Q000502:physiology*; D054884:Host-Pathogen Interactions; D006801:Humans; D048348:Reverse Transcription; D016662:Virus Integration
chemical_list: D017868:Cyclic AMP-Dependent Protein Kinases