Nitric Oxide Donor, (±)-S-Nitroso-N-acetylpenicillamine, Stabilizes Transactive Hypoxia-Inducible Factor-1α by Inhibiting von Hippel-Lindau Recruitment and Asparagine Hydroxylation

• DOI: 10.1124/mol.108.045278
• Publication Date: 2008-04-22T00:25:58Z
• Authors: Young-Kwon Park; Dae-Ro Ahn; Myoungsuk Oh; Taekyoung Lee; Eun Gyeong Yang; Miwon Son; Hyunsung Park
• Keywords: Hydroxylation; Snap; Hypoxia-Inducible Factors

We have confirmed that the NO donor (±)-<i>S</i>-nitroso-<i>N</i>-acetylpenicillamine (SNAP) stabilizes transactive form of hypoxia-inducible factor-1α (HIF-1α), leading to induction HIF-1α target genes such as vascular endothelial growth factor and carbonic anhydrase 9. Activation should require inhibition dual system keeps it inactive. One is ubiquitination, which triggered by hydroxylation HIF-1α-proline subsequent binding E3 ubiquitin ligase, von Hippel Lindau (VHL) protein. The other HIF-1α-asparagine, reduces affinity for its coactivator, cAMP responsive element protein/p300. examined effects SNAP on proline asparagine peptides measuring activities corresponding enzymes, HIF-1α-specific hydroxylase 2 (PHD2) hydroxylase, designated inhibiting (FIH-1), respectively. found did not prevent PHD2 from hydroxylating HIF-1α. Instead, blocked interaction between VHL proline-hydroxylated HIF-1α, but only when reducing agents Fe(II) vitamin C were limiting. fact absence cysteine 520 abolishes responsiveness suggests this residue mediates presumably <i>S</i>-nitrosylation Un-like PHD2, FIH-1 was directly inhibited SNAP, again Substitution 800 with alanine failed reverse inhibitory hydroxylation, implying FIH-1, substrate SNAP.