Modulation of p300 binding by posttranslational modifications of the C-terminal activation domain of hypoxia-inducible factor-1alpha.
Posttranslational modifications of hypoxia-inducible factor-1alpha (HIF-1alpha) influence HIF-mediated transcription, likely by affecting binding to p300/cAMP-response element-binding protein (CBP). To systematically analyze the HIF-1alpha-p300/CBP interaction, we developed a fluorescence polarization-based binding assay, employing fluorescein-labeled peptides derived from the C-terminal transactivation domain (C-TAD) of HIF-1alpha. After optimized for effectively capturing p300/CBP, the assay was utilized for evaluating direct effects of posttranslational modifications of the HIF-1alpha C-TAD on p300 binding. The results demonstrated that asparagine hydroxylation and S-nitrosylation of HIF-1alpha decrease p300 binding, while its phosphorylation does not affect p300 binding, which was reconfirmed by competitive inhibition analyses using mutant peptides.
Cho
Hyunju
H
Life Sciences Division, Korea Institute of Science and Technology, Seoul, Republic of Korea.
Ahn
Dae-Ro
DR
Park
Hyunsung
H
Yang
Eun Gyeong
EG
D020816:Amino Acid Motifs; D001216:Asparagine / Q000737:chemistry / Q000378:metabolism; D001667:Binding, Competitive; D050881:E1A-Associated p300 Protein / Q000737:chemistry*; D005453:Fluorescence; D006801:Humans; D006900:Hydroxylation; D051795:Hypoxia-Inducible Factor 1, alpha Subunit / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D009584:Nitrogen / Q000737:chemistry; D010455:Peptides / Q000737:chemistry / Q000235:genetics; D010766:Phosphorylation; D011485:Protein Binding; D011499:Protein Processing, Post-Translational; D017434:Protein Structure, Tertiary; D050880:p300-CBP Transcription Factors / Q000737:chemistry
C497442:HIF1A protein, human; D051795:Hypoxia-Inducible Factor 1, alpha Subunit; D010455:Peptides; D001216:Asparagine; D050881:E1A-Associated p300 Protein; C494360:EP300 protein, human; D050880:p300-CBP Transcription Factors; D009584:Nitrogen