title: S-nitrosation of Cys-800 of HIF-1alpha protein activates its interaction with p300 and stimulates its transcriptional activity.
abstract: Hypoxia inducible factor 1 (HIF-1) is a heterodimeric transcriptional complex that plays pivotal role in the regulation of cellular utilization of oxygen as well as glucose and is an essential regulator of angiogenesis in solid tumor and ischemic disorders. Recently HIF-1alpha, a subunit of HIF-1 complex, was characterized as a potential target for S-nitrosation, providing no information about the impact of this posttranslational modification on the protein transactivation. Cys-800 of HIF-1alpha protein has reactive SH-group, which is critical for the recruitment of p300 co-activator that is necessary for transcriptional activity of HIF-1 complex. Here we report that S-nitrosation of Cys-800 activates HIF-1alpha-p300 interaction and stimulates protein transactivation. We have found that S-nitrosation of the HIF-1alpha C-terminal domain by nitric oxide derived from donors and nitric oxide synthase increases protein transcriptional activity. The increase of HIF-1 transcriptional activity was not observed in the case of Cys-800 substitution to Ala, though other protein thiol groups were nitrosated. Experiments with GST pull-down assay suggest that S-nitrosation of Cys-800 stimulates the recruitment of p300 co-activator protein to the HIF-1alpha C-terminal domain.
authors.affiliation: Department of Biochemistry, Mechnikov Odessa National University, Apt 208, Glushko prospect 16, Odessa 65104, Ukraine.
authors.forename: Inna M
authors.initials: IM
authors.lastname: Yasinska
authors.forename: Vadim V
authors.initials: VV
authors.lastname: Sumbayev
mesh_terms: D001665:Binding Sites; D002460:Cell Line; D003545:Cysteine / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D004790:Enzyme Induction; D006801:Humans; D051793:Hypoxia-Inducible Factor 1; D051795:Hypoxia-Inducible Factor 1, alpha Subunit; D009569:Nitric Oxide / Q000378:metabolism*; D019001:Nitric Oxide Synthase / Q000096:biosynthesis / Q000502:physiology; D015538:Nitrosation; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism*; D011485:Protein Binding; D011499:Protein Processing, Post-Translational; D021122:Protein Subunits / Q000235:genetics / Q000378:metabolism; D015534:Trans-Activators / Q000378:metabolism*; D014157:Transcription Factors; D015533:Transcriptional Activation; D014162:Transfection
chemical_list: D004268:DNA-Binding Proteins; C497442:HIF1A protein, human; D051793:Hypoxia-Inducible Factor 1; D051795:Hypoxia-Inducible Factor 1, alpha Subunit; D009687:Nuclear Proteins; D021122:Protein Subunits; D015534:Trans-Activators; D014157:Transcription Factors; D009569:Nitric Oxide; D019001:Nitric Oxide Synthase; D003545:Cysteine