Characterization of the mouse nuclear orphan receptor TR2-11 gene promoter and its potential role in retinoic acid-induced P19 apoptosis

The Rev-erb and retinoic acid-related orphan receptors (ROR) are two related families of orphan nuclear receptors that recognize similar response elements but have opposite effects on transcription. Recently, theRev-erbαgene promoter has been characterized and shown to harbor a functional Rev-erbα-binding site known as Rev-DR2, responsible for negative feedback down-regulation of promoter activity by Rev-erbα itself. The present study aimed to investigate whetherRev-erbαgene expression is regulated by RORα. Gel shift analysis demonstrated thatin vitrotranslated hRORα1 protein binds to the Rev-DR2 site, both as monomer and dimer. Chromatin immunoprecipitation assays demonstrated that binding of RORα to this site also occurredin vivoin human hepatoma HepG2 cells. The Rev-DR2 site was further shown to be functional as it conferred hRORα1 responsiveness to a heterologous promoter and to the natural humanRev-erbαgene promoter in these cells. Mutation of this site in the context of the naturalRev-erbαgene promoter abolished its activation by RORα, indicating that this site plays a key role in hRORα1 action. Finally, adenoviral overexpression of hRORα1 in HepG2 cells led to enhanced hRev-erbα mRNA accumulation, further confirming the physiological importance of RORα1 in the regulation of Rev-erbα expression.

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Identification and Characterization of a Second Retinoic Acid Response Element in the Phosphoenolpyruvate Carboxykinase Gene Promoter

Journal of Biological Chemistry ◽

10.1074/jbc.271.11.6260 ◽

1996 ◽

Vol 271 (11) ◽

pp. 6260-6264 ◽

Cited By ~ 43

Author(s):

Donald K. Scott ◽

John A. Mitchell ◽

Daryl K. Granner

Keyword(s):

Retinoic Acid ◽

Phosphoenolpyruvate Carboxykinase ◽

Gene Promoter ◽

Response Element ◽

Retinoic Acid Response Element ◽

Identification And Characterization ◽

Phosphoenolpyruvate Carboxykinase Gene

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Identification and Characterization of a Versatile Retinoid Response Element (Retinoic Acid Receptor Response Element-Retinoid X Receptor Response Element) in the Mouse Tissue Transglutaminase Gene Promoter

Journal of Biological Chemistry ◽

10.1074/jbc.271.8.4355 ◽

1996 ◽

Vol 271 (8) ◽

pp. 4355-4365 ◽

Cited By ~ 92

Author(s):

Laszlo Nagy ◽

Margaret Saydak ◽

Nancy Shipley ◽

Shan Lu ◽

James P. Basilion ◽

...

Keyword(s):

Retinoic Acid ◽

Retinoic Acid Receptor ◽

Tissue Transglutaminase ◽

Gene Promoter ◽

Retinoid X Receptor ◽

Mouse Tissue ◽

Response Element ◽

Receptor Response ◽

Identification And Characterization

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Coactivation of SF-1-Mediated Transcription of Steroidogenic Enzymes by Ubc9 and PIAS1

Endocrinology ◽

10.1210/en.2010-1232 ◽

2011 ◽

Vol 152 (6) ◽

pp. 2266-2277 ◽

Cited By ~ 13

Author(s):

Noriko Suda ◽

Hirotaka Shibata ◽

Isao Kurihara ◽

Yayoi Ikeda ◽

Sakiko Kobayashi ◽

...

Keyword(s):

Adrenal Cortex ◽

Gene Promoter ◽

Orphan Receptor ◽

Mrna Levels ◽

Steroidogenic Enzyme ◽

Steroidogenic Factor 1 ◽

Cyp17 Gene ◽

Nuclear Orphan Receptor ◽

Interfering Rna

Steroidogenic factor-1 (SF-1) is a nuclear orphan receptor, which is essential for adrenal development and regulation of steroidogenic enzyme expression. SF-1 is posttranslationally modified by small ubiquitin-related modifier-1 (SUMO-1), thus mostly resulting in attenuation of transcription. We investigated the role of sumoylation enzymes, Ubc9 and protein inhibitors of activated STAT1 (PIAS1), in SF-1-mediated transcription of steroidogenic enzyme genes in the adrenal cortex. Coimmunoprecipitation assays showed that both Ubc9 and PIAS1 interacted with SF-1. Transient transfection assays in adrenocortical H295R cells showed Ubc9 and PIAS1 potentiated SF-1-mediated transactivation of reporter constructs containing human CYP17, CYP11A1, and CYP11B1 but not CYP11B2 promoters. Reduction of endogenous Ubc9 and PIAS1 by introducing corresponding small interfering RNA significantly reduced endogenous CYP17, CYP11A1, and CYP11B1 mRNA levels, indicating that they normally function as coactivators of SF-1. Wild type and sumoylation-inactive mutants of Ubc9 and PIAS1 can similarly enhance the SF-1-mediated transactivation of the CYP17 gene, indicating that the coactivation potency of Ubc9 and PIAS1 is independent of sumoylation activity. Chromatin immunoprecipitation assays demonstrated that SF-1, Ubc9, and PIAS1 were recruited to an endogenous CYP17 gene promoter in the context of chromatin in vivo. Immunohistochemistry and Western blotting showed that SF-1, Ubc9, and PIAS1 were expressed in the nuclei of the human adrenal cortex. In cortisol-producing adenomas, the expression pattern of SF-1 and Ubc9 were markedly increased, whereas that of PIAS1 was decreased compared with adjacent normal adrenals. These results showed the physiological roles of Ubc9 and PIAS1 as SF-1 coactivators beyond sumoylation enzymes in adrenocortical steroidogenesis and suggested their possible pathophysiological roles in human cortisol-producing adenomas.

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