title: Heterogenous nuclear ribonucleoprotein Q increases protein expression from HIV-1 Rev-dependent transcripts.
abstract: BACKGROUND
  Heterogenous nuclear ribonucleoproteins (hnRNPs) control many processes of the gene expression machinery including mRNA transcription, splicing, export, stability and translation. Recent data show interaction of the HIV-1 Rev regulatory protein with a subset of hnRNP proteins, that includes hnRNP Q, suggesting that hnRNPs can contribute to regulation of HIV-1 gene expression by Rev.
  
  
  RESULTS
  In this work we address the effect of hnRNP Q on Rev-dependent gene expression. We show that hnRNP Q overexpression increased levels of proteins produced from a Rev-dependent reporter gene in the presence of Rev. Increased protein levels did not correlate with changes in either the levels or the nucleocytoplasmic distribution of Rev-dependent reporter mRNAs. Similar observations were made in persistently HIV-1 infected HeLa cells. In these cells, hnRNP Q overexpression increased levels of the HIV-1 Gag-p24 protein, while levels of viral Rev-dependent mRNAs were not affected.
  
  
  CONCLUSIONS
  Our data indicate that hnRNP Q can stimulate the protein production of Rev-dependent mRNAs without changing mRNA levels and mRNA export, respectively. This suggests that hnRNP Q can boost HIV gene expression at the level of protein production.
authors.affiliation: Institute of Virology, Helmholtz Zentrum München, Research Center for Environmental Health, Ingolstaedter Landstraße 1, 85764 Neuherberg, Germany.
authors.forename: Michelle
authors.initials: M
authors.lastname: Vincendeau
authors.forename: Daniel
authors.initials: D
authors.lastname: Nagel
authors.forename: Jara K
authors.initials: JK
authors.lastname: Brenke
authors.forename: Ruth
authors.initials: R
authors.lastname: Brack-Werner
authors.forename: Kamyar
authors.initials: K
authors.lastname: Hadian
mesh_terms: D019677:Artificial Gene Fusion; D004847:Epithelial Cells / Q000821:virology; D015967:Gene Expression Regulation, Viral; D017930:Genes, Reporter; D006367:HeLa Cells; D034441:Heterogeneous-Nuclear Ribonucleoproteins / Q000378:metabolism*; D054884:Host-Pathogen Interactions; D006801:Humans; D014764:Viral Proteins / Q000096:biosynthesis*; D054321:rev Gene Products, Human Immunodeficiency Virus / Q000378:metabolism*
chemical_list: D034441:Heterogeneous-Nuclear Ribonucleoproteins; C425312:SYNCRIP protein, human; D014764:Viral Proteins; D054321:rev Gene Products, Human Immunodeficiency Virus; C514860:rev protein, Human Immunodeficiency Virus-1