Endogenous Purification of NR4A2 (Nurr1) Identified Poly(ADP-Ribose) Polymerase 1 as a Prime Coregulator in Human Adrenocortical H295R Cells

Abstract

Aldosterone is synthesized in zona glomerulosa of adrenal cortex in response to angiotensin II. This stimulation transcriptionally induces expression of a series of steroidogenic genes such as HSD3B and CYP11B2 via NR4A (nuclear receptor subfamily 4 group A) nuclear receptors and ATF (activating transcription factor) family transcription factors. Nurr1 belongs to the NR4A family and is regarded as an orphan nuclear receptor. The physiological significance of Nurr1 in aldosterone production in adrenal cortex has been well studied. However, coregulators supporting the Nurr1 function still remain elusive. In this study, we performed RIME (rapid immunoprecipitation mass spectrometry of endogenous proteins), a recently developed endogenous coregulator purification method, in human adrenocortical H295R cells and identified PARP1 as one of the top Nurr1-interacting proteins. Nurr1-PARP1 interaction was verified by co-immunoprecipitation. In addition, both siRNA knockdown of PARP1 and treatment of AG14361, a specific PARP1 inhibitor suppressed the angiotensin II-mediated target gene induction in H295R cells. Furthermore, PARP1 inhibitor also suppressed the aldosterone secretion in response to the angiotensin II. Together, these results suggest PARP1 is a prime coregulator for Nurr1.

The physiological and pathophysiological roles of carbohydrate response element binding protein in the kidney

“…For tissue-specific regulation of ChREBP activity, further analysis of the molecular mechanisms of ChREBP regulation in each tissue is required. Given that transcription factors generally form transcriptional coregulator complexes in a tissue-specific manner [64][65][66][67], it would be of interest to search for such protein complexes which ChREBP forms using a proteomic approach [67][68][69][70][71], and to determine whether these complexes could be a potential drug target for tissue-specific ChREBP activation/ inhibition.…”

Identification and Functional Characterization of a Novel Androgen Receptor Coregulator, EAP1

“…The RIME experiments were performed as reported previously [ 50 ]. Briefly, 5 × 10 7 cells were stimulated with DHT for 8 hours and then fixed in 1% formalin for 8 minutes at 37 °C.…”

Molecular Mechanisms of Functional Adrenocortical Adenoma and Carcinoma: Genetic Characterization and Intracellular Signaling Pathway

“…However, there are few reports on the analysis of transcriptional activation complexes in the adrenal gland for both NGFIB and NURR1, and the details of transcription factor complexes that may affect gene expression, such as CYP11B2 , still remain unknown. In 2018, we identified poly (ADP-ribose) polymerase 1 (PARP1) as a transcription factor complex of NURR1 in H295R cells [ 52 ] ( Figure 5 ). This is an in vitro study, but it could contribute to our understanding of the unknown transcription factor complex of NURR1.…”

“…Among them, NURR1 is a nuclear receptor whose expression increases when the intracellular calcium concentration transcriptional activity increases. NURR1 also interacts with PARP1 to regulate the transcriptional activity of target genes [ 52 ]. In vitro, it has been reported that inhibitors of PARP1 suppress aldosterone secretion by suppressing the expression of HSD3B1 and CYP11B2 [ 52 ].…”

“…NURR1 also interacts with PARP1 to regulate the transcriptional activity of target genes [ 52 ]. In vitro, it has been reported that inhibitors of PARP1 suppress aldosterone secretion by suppressing the expression of HSD3B1 and CYP11B2 [ 52 ]. In addition, bortezomib was reported to decrease CYP11B2 gene expression by altering the epigenomic state upstream of the CYP11B2 gene [ 59 ].…”