scholarly journals Conformational Changes of RORγ During Response Element Recognition and Coregulator Engagement.

2021 ◽  
Author(s):  
Timothy S Strutzenberg ◽  
Scott J Novick ◽  
Ruben D Garcia-Ordonez ◽  
Christelle Doebelin ◽  
Yuanjun He ◽  
...  

The retinoic acid receptor-related orphan receptorγ (RORγ) is a ligand-dependent transcription factor of the nuclear receptor super family that underpins metabolic activity, immune function, and cancer progression. Despite being a valuable drug target in health and disease, our understanding of the ligand-dependent activities of RORγ is far from complete. Like most nuclear receptors, RORγ must recruit coregulatory protein to enact the RORγ target gene program. To date, a majority of structural studies have been focused exclusively on the RORγ ligand-binding domain and the ligand-dependent recruitment of small peptide segments of coregulators. Herein, we examine the ligand-dependent assembly of full length RORγ:coregulator complexes on cognate DNA response elements using structural proteomics and small angle x-ray scattering. The results from our studies suggest that RORγ becomes elongated upon DNA recognition, preventing long range interdomain crosstalk. We also determined that the DNA binding domain adopts a sequence-specific conformation, and that coregulatory proteins may be able to sense the ligand- and DNA-bound status of RORγ. We propose a model where ligand-dependent coregulator recruitment may be influenced by the sequence of the DNA to which RORγ is bound. Overall, the efforts described herein will illuminate important aspects of full length RORγ and monomeric orphan nuclear receptor target gene regulation through DNA-dependent conformational changes.

2005 ◽  
Vol 186 (1) ◽  
pp. 33-42 ◽  
Author(s):  
Sinead N Kelly ◽  
T Joseph McKenna ◽  
Leonie S Young

The capacity of the adrenal to produce steroids is controlled in part through the transcriptional regulation of steroid enzymes. The orphan nuclear receptor steroidogenic factor 1 (SF-1) is central to the transcriptional regulation of all steroid hydroxylase enzymes, whereas nur77 can preferentially regulate steroid enzyme genes relevant to cortisol production. We hypothesised that, in the presence of secretagogues, SF-1 and nur77 may differentially interact with coregulatory proteins in the human adrenal cortex. Both coregulatory proteins, steroid receptor coactivator (SRC-1) and silencing mediator for retinoid and thyroid hormones (SMRT), were found to be expressed in the zona fasciculata and reticularis in the human adrenal cortex, but were largely absent from the zona glomerulosa. Both coregulatory proteins were colocalised with SF-1 and nur77. In the H295R adrenal tumour cell line, SF-1 and nur77 transcripts were increased in cells in the presence of forskolin, whereas nur77 mRNA was also induced with angiotensin II (AII). The coactivator SRC-1 mRNA was increased in the presence of both forskolin and AII. Forskolin induced recruitment of SRC-1 to the SF-1 response element and induced SRC-1–SF-1 interactions, whereas AII increased recruitment of SRC-1 to the nur77 response element and induced SRC-1–nur77 interactions. The corepressor SMRT interacted with SF-1 in the presence of AII and with nur77 in cells treated with forskolin. Orphan nuclear receptor–coregulatory protein interactions may have consequences for the regulation of key steroidogenic enzymes in the human adrenal cortex.


2020 ◽  
Vol 6 (18) ◽  
pp. eaaz8031 ◽  
Author(s):  
Leiming Wang ◽  
Chiang-Min Cheng ◽  
Jun Qin ◽  
Mafei Xu ◽  
Chung-Yang Kao ◽  
...  

The orphan nuclear receptor COUP-TFII is expressed at a low level in adult tissues, but its expression is increased and shown to promote progression of multiple diseases, including prostate cancer, heart failure, and muscular dystrophy. Suppression of COUP-TFII slows disease progression, making it an intriguing therapeutic target. Here, we identified a potent and specific COUP-TFII inhibitor through high-throughput screening. The inhibitor specifically suppressed COUP-TFII activity to regulate its target genes. Mechanistically, the inhibitor directly bound to the COUP-TFII ligand-binding domain and disrupted COUP-TFII interaction with transcription regulators, including FOXA1, thus repressing COUP-TFII activity on target gene regulation. Through blocking COUP-TFII’s oncogenic activity in prostate cancer, the inhibitor efficiently exerted a potent antitumor effect in xenograft mouse models and patient-derived xenograft models. Our study identified a potent and specific COUP-TFII inhibitor that may be useful for the treatment of prostate cancer and possibly other diseases.


2002 ◽  
Vol 65 (4) ◽  
pp. 1780-1788 ◽  
Author(s):  
Yoko Hirata ◽  
Michael Whalin ◽  
David D. Ginty ◽  
Jun Xing ◽  
Michael E. Greenberg ◽  
...  

Endocrinology ◽  
1997 ◽  
Vol 138 (10) ◽  
pp. 4138-4146 ◽  
Author(s):  
Yanzhuang Li ◽  
Lester F. Lau

Abstract ACTH treatment of Y1 adrenocortical cells induces the synthesis of Nur77, an orphan nuclear receptor that can act as a potent trans-activator for such genes as 21-hydroxylase (CYP21). Nur77 has thus been proposed to be a mediator of ACTH action in activating the expression of genes that encode steroidogenic enzymes. Here we show that ACTH regulates the activity of Nur77 at the level of phosphorylation. ACTH induces the synthesis of transcriptionally active, DNA-binding Nur77 that is unphosphorylated at Ser354, which resides within the DNA-binding domain. By contrast, the Nur77 population that is constitutively present in Y1 cells is phosphorylated at Ser354 and does not bind DNA. Substitutions of Ser354 with negatively charged amino acids, such as Asp or Glu, dramatically decreased Nur77 DNA-binding and trans-activation activities, whereas mutation to the neutral Ala had no effect. Aside from phosphorylation within the DNA-binding domain, ACTH treatment does not induce modifications in the N- and C-terminal domains of Nur77 that significantly affect activity. Although the specific kinases that phosphorylate Nur77 in vivo are not known, the mitogen-activated protein kinase/pp90RSK pathway is not critical to Nur77 regulation. We propose that ACTH treatment of Y1 cells results in modulation of the activities of both kinases and phosphatases, which, in turn, regulate the activities of such transcription factors as Nur77.


2008 ◽  
Vol 106 (3) ◽  
pp. 1017-1026 ◽  
Author(s):  
Po-Cheng Lin ◽  
Yi-Lin Chen ◽  
Shao-Chih Chiu ◽  
Yung-Luen Yu ◽  
Shee-Ping Chen ◽  
...  

Development ◽  
1995 ◽  
Vol 121 (3) ◽  
pp. 839-853 ◽  
Author(s):  
A.P. Monaghan ◽  
E. Grau ◽  
D. Bock ◽  
G. Schutz

The Drosophila tailless gene is a member of the orphan nuclear receptor subfamily. In Drosophila, the tailless gene is required for pattern formation in embryonic poles. During development, tailless is activated in the termini of the embryo in response to the torso receptor tyrosine kinase signal transduction cascade. Recessive mutations of tailless result in abnormalities in anterior portions of the head and in all structures posterior to the eighth abdominal segment. Localised expression of tailless is required in combination with a second terminal gene, huckebein, to control the expression of downstream genes. We have isolated a mouse homolog of the Drosophila tailless gene, which shows considerable homology in the DNA-binding domain suggesting that the respective proteins bind similar recognition sequences. Although the ligand-binding domain shows features in common with the tailless ligand domain, it also shares conserved amino acid stretches with other orphan nuclear receptors, the human ovalbumin upstream binding protein transcription factors (hCOUP-TF I and II). We have analysed the expression of taillees in mice, and show that it is specifically localised to the developing forebrain from day 8 p.c. and in dorsal midbrain from day 8.75 p.c. To define the anterior and posterior boundaries of expression, we compared the expression pattern of tailless to those of other forebrain markers, including distal-less (Dlx1), brain factor 1 (BF1), and the orthodenticle genes (Otx1 and Otx2). In addition to the developing forebrain, these genes show dynamic patterns of expression in two structures whose development requires inductive signals from the forebrain: the eye and the nose. These results suggest that the mouse taillees gene may be required to pattern anterior brain differentiation.


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