Retinoic acid activates human inducible nitric oxide synthase gene through binding of RARalpha/RXRalpha heterodimer to a novel retinoic acid response element in the promoter.
Human inducible nitric oxide synthase (hiNOS) catalyzes nitric oxide (NO) which has a significant effect on tumor suppression and cancer therapy. Here we revealed the detailed molecular mechanism involved in the regulation of hiNOS expression induced by retinoic acid (RA). We showed that RARalpha/RXRalpha heterodimer was important in hiNOS promoter activation, hiNOS protein expression, and NO production. Serial deletion and site-directed mutation analysis revealed two half-sites of retinoic acid response element (RARE) spaced by 5bp located at -172 to -156 in the hiNOS promoter. EMSA and ChIP assays demonstrated that RARalpha/RXRalpha directly bound to this RARE of hiNOS promoter. Our results suggested the identification of a novel RARE in the hiNOS promoter and the roles of the nuclear receptors (RARalpha/RXRalpha) in the induction of hiNOS by RA.
Zou
Fang
F
State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan 430072, PR China.
Liu
Yan
Y
Liu
Li
L
Wu
Kailang
K
Wei
Wei
W
Zhu
Ying
Y
Wu
Jianguo
J
D001483:Base Sequence; D017931:DNA Primers; D019281:Dimerization; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects*; D006367:HeLa Cells; D006801:Humans; D052247:Nitric Oxide Synthase Type II / Q000235:genetics*; D016133:Polymerase Chain Reaction; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D012333:RNA, Messenger / Q000235:genetics; D018168:Receptors, Retinoic Acid / Q000378:metabolism*; D000072482:Retinoic Acid Receptor alpha; D047488:Retinoid X Receptors / Q000378:metabolism*; D014212:Tretinoin / Q000494:pharmacology*
D017931:DNA Primers; C000607071:RARA protein, human; D012333:RNA, Messenger; D018168:Receptors, Retinoic Acid; D000072482:Retinoic Acid Receptor alpha; D047488:Retinoid X Receptors; D014212:Tretinoin; D052247:Nitric Oxide Synthase Type II