title: Targeting deoxyhypusine hydroxylase activity impairs cap-independent translation initiation driven by the 5'untranslated region of the HIV-1, HTLV-1, and MMTV mRNAs.
abstract: Replication of the human immunodeficiency virus type 1 (HIV-1) is dependent on eIF5A hypusination. Hypusine is formed post-translationally on the eIF5A precursor by two consecutive enzymatic steps; a reversible reaction involving the enzyme deoxyhypusine synthase (DHS) and an irreversible step involving the enzyme deoxyhypusine hydroxylase (DOHH). In this study we explored the effect of inhibiting DOHH activity and therefore eIF5A hypusination, on HIV-1 gene expression. Results show that the expression of proteins from an HIV-1 molecular clone is reduced when DOHH activity is inhibited by Deferiprone (DFP) or Ciclopirox (CPX). Next we evaluated the requirement of DOHH activity for internal ribosome entry site (IRES)-mediated translation initiation driven by the 5'untranslated region (5'UTR) of the full length HIV-1 mRNA. Results show that HIV-1 IRES activity relies on DOHH protein concentration and enzymatic activity. Similar results were obtained for IRES-dependent translation initiation mediated by 5'UTR of the human T-cell lymphotropic virus type 1 (HTLV-1) and the mouse mammary tumor virus (MMTV) mRNAs. Interestingly, activity of the poliovirus IRES, was less sensitive to the targeting of DOHH suggesting that not all viral IRESs are equally dependent on the cellular concentration or the activity of DOHH. In summary we present evidence indicating that the cellular concentration of DOHH and its enzymatic activity play a role in HIV-1, HTLV-1 and MMTV IRES-mediated translation initiation.
authors.affiliation: Laboratorio de Virología Molecular, Instituto Milenio de Inmunología e Inmunoterapia, Departamento de Enfermedades Infecciosas e Inmunología Pediátrica, Escuela de Medicina, Pontificia Universidad Católica de Chile, Marcoleta 391, Santiago, Chile.
authors.forename: C Joaquín
authors.initials: CJ
authors.lastname: Cáceres
authors.affiliation: Laboratorio de Virología Molecular, Instituto Milenio de Inmunología e Inmunoterapia, Departamento de Enfermedades Infecciosas e Inmunología Pediátrica, Escuela de Medicina, Pontificia Universidad Católica de Chile, Marcoleta 391, Santiago, Chile.
authors.forename: Jenniffer
authors.initials: J
authors.lastname: Angulo
authors.affiliation: Laboratorio de Virología Molecular, Instituto Milenio de Inmunología e Inmunoterapia, Departamento de Enfermedades Infecciosas e Inmunología Pediátrica, Escuela de Medicina, Pontificia Universidad Católica de Chile, Marcoleta 391, Santiago, Chile.
authors.forename: Nataly
authors.initials: N
authors.lastname: Contreras
authors.affiliation: Laboratorio de Virología Molecular, Instituto Milenio de Inmunología e Inmunoterapia, Departamento de Enfermedades Infecciosas e Inmunología Pediátrica, Escuela de Medicina, Pontificia Universidad Católica de Chile, Marcoleta 391, Santiago, Chile.
authors.forename: Karla
authors.initials: K
authors.lastname: Pino
authors.affiliation: Laboratorio de Virología Molecular, Instituto Milenio de Inmunología e Inmunoterapia, Departamento de Enfermedades Infecciosas e Inmunología Pediátrica, Escuela de Medicina, Pontificia Universidad Católica de Chile, Marcoleta 391, Santiago, Chile.
authors.forename: Jorge
authors.initials: J
authors.lastname: Vera-Otarola
authors.affiliation: Laboratorio de Virología Molecular, Instituto Milenio de Inmunología e Inmunoterapia, Departamento de Enfermedades Infecciosas e Inmunología Pediátrica, Escuela de Medicina, Pontificia Universidad Católica de Chile, Marcoleta 391, Santiago, Chile. Electronic address: malopez@med.puc.cl.
authors.forename: Marcelo
authors.initials: M
authors.lastname: López-Lastra
mesh_terms: D020121:5' Untranslated Regions; D000818:Animals; D000077768:Ciclopirox; D000077543:Deferiprone; D015870:Gene Expression; D057809:HEK293 Cells; D015497:HIV-1 / Q000187:drug effects / Q000235:genetics* / Q000502:physiology*; D006367:HeLa Cells; D015368:Human T-lymphotropic virus 1 / Q000235:genetics*; D006801:Humans; D008324:Mammary Tumor Virus, Mouse / Q000187:drug effects / Q000235:genetics*; D051379:Mice; D006899:Mixed Function Oxygenases / Q000037:antagonists & inhibitors* / Q000187:drug effects; D010448:Peptide Initiation Factors / Q000187:drug effects; D014176:Protein Biosynthesis / Q000187:drug effects; D011728:Pyridones / Q000494:pharmacology; D012333:RNA, Messenger / Q000187:drug effects; D016601:RNA-Binding Proteins / Q000187:drug effects; D000097574:Eukaryotic Translation Initiation Factor 5A
chemical_list: D020121:5' Untranslated Regions; D000077768:Ciclopirox; D000077543:Deferiprone; D006899:Mixed Function Oxygenases; D010448:Peptide Initiation Factors; D011728:Pyridones; D012333:RNA, Messenger; D016601:RNA-Binding Proteins; D000097574:Eukaryotic Translation Initiation Factor 5A; C047991:deoxyhypusine hydroxylase
keywords: DOHH; HIV-1; HTLV-1 MMTV; IRES; Protein synthesis; RNA; eIF5A