The Nuclear Receptor COUP-TFII Regulates Amhr2 Gene Transcription via a GC-Rich Promoter Element in Mouse Leydig Cells

Abstract The nuclear receptor chicken ovalbumin upstream promoter–transcription factor type II (COUP-TFII)/NR2F2 is expressed in adult Leydig cells, and conditional deletion of the Coup-tfii/Nr2f2 gene impedes their differentiation. Steroid production is also reduced in COUP-TFII–depleted Leydig cells, supporting an additional role in steroidogenesis for this transcription factor. COUP-TFII action in Leydig cells remains to be fully characterized. In the present work, we report that COUP-TFII is an essential regulator of the gene encoding the anti-Müllerian hormone receptor type 2 (Amhr2), which participates in Leydig cell differentiation and steroidogenesis. We found that Amhr2 mRNA levels are reduced in COUP-TFII–depleted MA-10 Leydig cells. Consistent with this, COUP-TFII directly activates a −1486 bp fragment of the mouse Amhr2 promoter in transient transfection assays. The COUP-TFII responsive region was localized between −67 and −34 bp. Chromatin immunoprecipitation assay confirmed COUP-TFII recruitment to the proximal Amhr2 promoter whereas DNA precipitation assay revealed that COUP-TFII associates with the −67/−34 bp region in vitro. Even though the −67/−34 bp region contains an imperfect nuclear receptor element, COUP-TFII–mediated activation of the Amhr2 promoter requires a GC-rich sequence at −39 bp known to bind the specificity protein (SP)1 transcription factor. COUP-TFII transcriptionally cooperates with SP1 on the Amhr2 promoter. Mutations that altered the GCGGGGCGG sequence at −39 bp abolished COUP-TFII–mediated activation, COUP-TFII/SP1 cooperation, and reduced COUP-TFII binding to the proximal Amhr2 promoter. Our data provide a better understanding of the mechanism of COUP-TFII action in Leydig cells through the identification and regulation of the Amhr2 promoter as a novel target.

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The INSL3 gene is a direct target for the orphan nuclear receptor, COUP-TFII, in Leydig cells

Journal of Molecular Endocrinology ◽

10.1530/jme-13-0290 ◽

2014 ◽

Vol 53 (1) ◽

pp. 43-55 ◽

Cited By ~ 19

Author(s):

Raifish E Mendoza-Villarroel ◽

Mickaël Di-Luoffo ◽

Etienne Camiré ◽

Xavier C Giner ◽

Catherine Brousseau ◽

...

Keyword(s):

Nuclear Receptor ◽

Protein Interactions ◽

Leydig Cells ◽

Molecular Mechanisms ◽

Direct Repeat ◽

Testicular Descent ◽

Mrna Levels ◽

Orphan Nuclear Receptor ◽

Protein Protein Interactions ◽

Dna Precipitation

Insulin-like 3 (INSL3), a hormone produced by Leydig cells, regulates testicular descent during foetal life and bone metabolism in adults. Despite its importance, little is known about the molecular mechanisms controlling INSL3 expression. Reduced Insl3 mRNA levels were reported in the testis of mice deficient for chicken ovalbumin upstream promoter-transcription factor II (COUP-TFII), an orphan nuclear receptor known to play critical roles in cell differentiation and lineage determination in several tissues. Although COUP-TFII-deficient mice had Leydig cell dysfunction and impaired fertility, it remained unknown whether Insl3 expression was directly regulated by COUP-TFII. In this study, we observed a significant decrease in Insl3 mRNA levels in MA-10 Leydig cells depleted of COUP-TFII. Furthermore, a −1087 bp mouse Insl3 promoter was activated fourfold by COUP-TFII in MA-10 Leydig cells. Using 5′ progressive deletions, the COUP-TFII-responsive element was located between −186 and −79 bp, a region containing previously uncharacterised direct repeat 0-like (DR0-like) and DR3 elements. The recruitment and direct binding of COUP-TFII to the DR0-like element were confirmed by chromatin immunoprecipitation and DNA precipitation assay respectively. Mutation of the DR0-like element, which prevented COUP-TFII binding, significantly decreased COUP-TFII-mediated activation of the −1087 bp Insl3 reporter in CV-1 fibroblast cells but not in MA-10 Leydig cells. Finally, we found that COUP-TFII cooperates with the nuclear receptor steroidogenic factor 1 (SF1) to further enhance Insl3 promoter activity. Our results identify Insl3 as a target for COUP-TFII in Leydig cells and revealed that COUP-TFII acts through protein–protein interactions with other DNA-bound transcription factors, including SF1, to activate Insl3 transcription in these cells.

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Cystine/glutamate antiporter xCT (SLC7A11) facilitates oncogenic RAS transformation by preserving intracellular redox balance

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1821323116 ◽

2019 ◽

Vol 116 (19) ◽

pp. 9433-9442 ◽

Cited By ~ 47

Author(s):

Jonathan K. M. Lim ◽

Alberto Delaidelli ◽

Sean W. Minaker ◽

Hai-Feng Zhang ◽

Milena Colovic ◽

...

Keyword(s):

Oxidative Stress ◽

Transcription Factor ◽

Redox Balance ◽

Gene Encoding ◽

Oncogenic Ras ◽

Opposing Effects ◽

Whole Transcriptome ◽

Intracellular Redox

The RAS family of proto-oncogenes are among the most commonly mutated genes in human cancers and predict poor clinical outcome. Several mechanisms underlying oncogenic RAS transformation are well documented, including constitutive signaling through the RAF-MEK-ERK proproliferative pathway as well as the PI3K-AKT prosurvival pathway. Notably, control of redox balance has also been proposed to contribute to RAS transformation. However, how homeostasis between reactive oxygen species (ROS) and antioxidants, which have opposing effects in the cell, ultimately influence RAS-mediated transformation and tumor progression is still a matter of debate and the mechanisms involved have not been fully elucidated. Here, we show that oncogenic KRAS protects fibroblasts from oxidative stress by enhancing intracellular GSH levels. Using a whole transcriptome approach, we discovered that this is attributable to transcriptional up-regulation of xCT, the gene encoding the cystine/glutamate antiporter. This is in line with the function of xCT, which mediates the uptake of cystine, a precursor for GSH biosynthesis. Moreover, our results reveal that the ETS-1 transcription factor downstream of the RAS-RAF-MEK-ERK signaling cascade directly transactivates the xCT promoter in synergy with the ATF4 endoplasmic reticulum stress-associated transcription factor. Strikingly, xCT was found to be essential for oncogenic KRAS-mediated transformation in vitro and in vivo by mitigating oxidative stress, as knockdown of xCT strongly impaired growth of tumor xenografts established from KRAS-transformed cells. Overall, this study uncovers a mechanism by which oncogenic RAS preserves intracellular redox balance and identifies an unexpected role for xCT in supporting RAS-induced transformation and tumorigenicity.

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Expression of Adhesive Pili and the Collagen-Binding Adhesin Ace Is Activated by ArgR Family Transcription Factors inEnterococcus faecalis

Journal of Bacteriology ◽

10.1128/jb.00269-18 ◽

2018 ◽

Vol 200 (18) ◽

Cited By ~ 6

Author(s):

Dawn A. Manias ◽

Gary M. Dunny

Keyword(s):

Transcription Factor ◽

Transcription Factors ◽

Enterococcus Faecalis ◽

Opportunistic Infections ◽

Structural Genes ◽

Gene Encoding ◽

Collagen Binding ◽

Content Type ◽

Surface Adhesins

ABSTRACTIt was shown previously that the disruption of theahrCgene encoding a predicted ArgR family transcription factor results in a severe defect in biofilm formationin vitro, as well as a significant attenuation of virulence ofEnterococcus faecalisstrain OG1RF in multiple experimental infection models. Using transcriptome sequencing (RNA-seq), we observedahrC-dependent changes in the expression of more than 20 genes. AhrC-repressed genes included predicted determinants of arginine catabolism and several other metabolic genes and predicted transporters, while AhrC-activated genes included determinants involved in the production of surface protein adhesins. Most notably, the structural and regulatory genes of theebplocus encoding adhesive pili were positively regulated, as well as theacegene, encoding a collagen-binding adhesin. UsinglacZtranscription reporter fusions, we determined thatahrCand a secondargRtranscription factor gene,argR2, both function to activate the expression ofebpR, which directly activates the transcription of the pilus structural genes. Our data suggest that in the wild-typeE. faecalis, the low levels of EbpR limit the expression of pili and that biofilm biomass is also limited by the amount of pili expressed by the bacteria. The expression ofaceis similarly enhanced by AhrC and ArgR2, butaceexpression is not dependent on EbpR. Our results demonstrate the existence of novel regulatory cascades controlled by a pair of ArgR family transcription factors that might function as a heteromeric protein complex.IMPORTANCECell surface adhesins play critical roles in the formation of biofilms, host colonization, and the pathogenesis of opportunistic infections byEnterococcus faecalis. Here, we present new results showing that the expression of two major enterococcal surface adhesins,ebppili, and the collagen-binding protein Ace is positively regulated at the transcription level by twoargRfamily transcription factors, AhrC and ArgR2. In the case of pili, the direct target of regulation is theebpRgene, previously shown to activate the transcription of the pilus structural genes, while the activation ofacetranscription appears to be directly impacted by the two ArgR proteins. These transcription factors may represent new targets for blocking enterococcal infections.

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A Conserved Mechanism of Transcription Factor Competition Controls Hematopoietic Progenitor Self-Renewal.

Blood ◽

10.1182/blood.v110.11.91.91 ◽

2007 ◽

Vol 110 (11) ◽

pp. 91-91

Author(s):

Shane R. Horman ◽

Chinamenveni S. Velu ◽

Tristan Bourdeau ◽

Avinash Baktula ◽

Jinfang Zhu ◽

...

Keyword(s):

Bone Marrow ◽

Transcription Factor ◽

Binding Sites ◽

Bone Marrow Cells ◽

Dominant Negative ◽

Wild Type ◽

Hematopoietic Progenitor ◽

Self Renewal ◽

Conditional Deletion

Abstract An intrinsic mechanism of self-renewal is critical for the maintenance of hematopoietic stem cells (HSC), but this HSC function is extinguished during differentiation of progenitors. Here we show that the self-renewal capacity of hematopoietic progenitor cells is regulated through physical competition for occupancy of select DNA binding sites. Initially, we found that conditional deletion of the Growth factor independent-1 (Gfi1) gene results in the accumulation of abnormally persistent myeloid progenitors in vivo. Specifically, while germline Gfi1 deletion induces defective HSC self renewal and a block to granulopoiesis, we find that conditional deletion of Gfi1 induces a severe but transient block to neutrophil development with repopulation of the bone marrow by the remaining wild type HSC within 8 weeks post deletion. However, even though normal levels of granulocyte colony forming units (G-CFU) returned by 8 weeks post deletion, an abnormal Gfi1−/− myeloid progenitor remained in the bone marrow in vivo. Subsequently, we find in vitro that both wild-type bone marrow cells expressing Gfi1-dominant-negative mutants, and Gfi1−/− Lin- bone marrow contain cells that replate indefinitely. We hypothesized that Gfi1 is critical to extinguish self renewal in hematopoietic progenitors. In seemingly unrelated work, we discovered antagonism between the drosophila orthologs of Gfi1 and the Hoxa9/Pbx1/Meis1 transcription factor complex during drosophila embryo segmentation. We extended our drosophila findings to discover that a subset of mammalian DNA regulatory sequences encode DNA binding sites for both Gfi1 and Hoxa9/Pbx1/Meis1. These DNA sequences are able to bind either factor, and function as a molecular switch. Interestingly, composite Gfi1/ Hoxa9/Pbx1/Meis1 binding sites are present in the regulatory regions of the gene encoding Hoxa9. We note that Gfi1 expression is normally induced, while Hoxa9 expression is down-regulated, during the transition from common myeloid progenitor (CMP) to the granulocyte-monocyte progenitor (GMP). CMP have greater self renewal potential than GMP. Conditional deletion of Gfi1 in sorted CMP or GMP both increases Hoxa9 expression and generates progenitors capable of replating indefinitely in vitro. Thus, Gfi1 is critical to limit self renewal in these progenitors. Deregulated Hoxa9 expression or activity appears pivotal to this new Gfi1-null phenotype, because Gfi1 dominant-negative mutants immortalize wild-type (or Hoxa7−/−) but not Hoxa9−/− bone marrow cells in vitro. An abnormal gain of self-renewal can unleash the leukemic potential of progenitor cells. We find that both limiting Gfi1 gene dosage and expression of Gfi1 dominant-negative mutants significantly increases Nup98-Hoxa9-mediated colony formation. In contrast, forced expression of Gfi1 prevents Nup98-Hoxa9 immortalization. Notably, the expression of Hoxa9 (independent of cases with Nup98-Hoxa9 fusions) has been reported to be of significant prognostic value in human acute myeloid leukemia. In conclusion, Gfi1 and the Hoxa9/Pbx1/Meis1 complex compete to control the expression of genes (such as Hoxa9) which are critical to extinguish self renewal and limit the leukemogenic potential of hematopoietic progenitors. The antagonism between these transcription factor complexes is conserved from drosophila segment formation to mammalian hematopoietic progenitor biology.

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Evaluation of relative roles of LH and FSH in regulation of differentiation of Leydig cells using an ethane 1,2-dimethylsulfonate-treated adult rat model

Journal of Endocrinology ◽

10.1677/joe.0.1760151 ◽

2003 ◽

Vol 176 (1) ◽

pp. 151-161 ◽

Cited By ~ 26

Author(s):

V Sriraman ◽

MR Sairam ◽

AJ Rao

Keyword(s):

Leydig Cells ◽

Serum Testosterone ◽

Side Chain ◽

Mrna Levels ◽

Rt Pcr ◽

Lh Receptor ◽

Side Chain Cleavage ◽

Chain Cleavage ◽

Cleavage Enzyme

The relative role of LH and FSH in regulation of differentiation of Leydig cells was assessed using an ethane 1,2-dimethylsulfonate (EDS)-treated rat model in which endogenous LH or FSH was neutralized from day 3 to day 22 following EDS treatment. Serum testosterone and the in vitro response of the purified Leydig cells to human chorionic gonadotropin (hCG) was monitored. In addition RNA was isolated from the Leydig cells to monitor the steady-state mRNA levels by RT-PCR for 17alpha-hydroxylase, side chain cleavage enzyme, steroidogenic acute regulatory protein (StAR), LH receptor, estrogen receptor (ER-alpha) and cyclophilin (internal control). Serum testosterone was undetected and the isolated Leydig cells secreted negligible amount of testosterone on stimulation with hCG in the group of rats that were treated with LH antiserum following EDS treatment. RT-PCR analysis revealed the absence of message for cholesterol side chain cleavage enzyme and 17alpha-hydroxylase although ER-alpha and LH receptor mRNA could be detected, indicating the presence of undifferentiated precursor Leydig cells. In contrast, the effects following deprival of endogenous FSH were not as drastic as seen following LH neutralization. Deprival of endogenous FSH in EDS-treated rats led to a significant decrease in serum testosterone and in vitro response to hCG by the Leydig cells. Also, there was a significant decrease in the steady-state mRNA levels of 17alpha-hydroxylase, cholesterol side chain cleavage enzyme, LH receptor and StAR as assessed by a semiquantitative RT-PCR. These results establish that while LH is obligatory for the functional differentiation of Leydig cells, repopulation of precursor Leydig cells is independent of LH, and also unequivocally establish an important role for FSH in regulation of Leydig cell function.

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Human and rat testis express two mRNA species encoding variants of NRD convertase, a metalloendopeptidase of the insulinase family

Biochemical Journal ◽

10.1042/bj3270773 ◽

1997 ◽

Vol 327 (3) ◽

pp. 773-779 ◽

Cited By ~ 14

Author(s):

Véronique HOSPITAL ◽

Annik PRAT ◽

Catherine JOULIE ◽

Dorra CHÉRIF ◽

Robert DAY ◽

...

Keyword(s):

Significant Degree ◽

Human Testis ◽

Mrna Levels ◽

Gene Encoding ◽

Peptide Substrates ◽

Rat Testis ◽

Processing Enzymes ◽

Nucleotide Insertion ◽

Testis Cdna

Rat testis NRD convertase (EC 3.4.24.61) is a Zn2+-dependent endopeptidase that cleaves, in vitro, peptide substrates at the N-terminus of Arg residues in dibasic sites. This putative processing enzyme of the insulinase family of metallopeptidases exhibits a significant degree of similarity to insulinase and two yeast processing enzymes, Axl1 and Ste23. We report the cloning of two human testis cDNA species encoding isoforms of NRD convertase, hNRD1 and hNRD2. Whereas the hNRD1 transcript (3.7 kb) is equivalent to the previously characterized rat cDNA (rNRD1), hNRD2 and rNRD2 are 3.9 kb novel forms containing a nucleotide insertion encoding a 68-residue segment. This motif, which is inserted N-terminal of the Zn2+-binding site, HXXEH, is contained within the most conserved region among the insulinase family members. Analysis of the deduced primary sequences revealed 92% identity between rat and human orthologues. The human gene encoding NRD convertase was localized to chromosome 1p32.1-p32.2. Whereas NRD convertase is mostly expressed in testis and in 24 cell lines, low mRNA levels were detected in most of the 27 other tissues tested.

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Slit/Robo signaling regulates Leydig cell steroidogenesis

Cell Communication and Signaling ◽

10.1186/s12964-020-00696-6 ◽

2021 ◽

Vol 19 (1) ◽

Author(s):

Emmanuelle Martinot ◽

Derek Boerboom

Keyword(s):

Cancer Progression ◽

Leydig Cell ◽

Leydig Cells ◽

Adult Mouse ◽

Primary Cultures ◽

Mouse Testis ◽

Mrna Levels ◽

Pathologic Processes ◽

In Vitro Treatment

Abstract Background First identified as a regulator of neuronal axon guidance, Slit/Robo signaling has since been implicated in additional physiologic and pathologic processes, such as angiogenesis, organogenesis and cancer progression. However, its roles in the regulation of testis function have been little explored. Methods Immunohistochemistry and RT-qPCR analyses were performed to detect the expression of Slit/Robo signaling effectors in the adult mouse testis. To identify the roles and mechanisms of Slit/Robo signaling in the regulation of steroidogenesis, RT-qPCR, immunoblotting and hormone measurements were carried out using Leydig cells (primary cultures and the MA10 cell line) treated with exogenous SLIT ligands, and testes from Robo1-null mice. Results Slit1, -2 and -3 and Robo1 and -2 expression was detected in the adult mouse testis, particularly in Leydig cells. In vitro treatment of Leydig cells with exogenous SLIT ligands led to a decrease in the expression of the steroidogenic genes Star, Cyp11a1, and Cyp17a1. SLIT2 treatment decreased the phosphorylation of the key steroidogenic gene regulator CREB, possibly in part by suppressing AKT activity. Furthermore, SLIT2 treatment reduced the responsiveness of MA10 cells to luteinizing hormone by decreasing the expression of Lhcgr. Consistent with these in vitro results, an increase in testicular Star mRNA levels and intra-testicular testosterone concentrations were found in Robo1-null mice. Finally, we showed that the expression of the Slit and Robo genes in Leydig cells is enhanced by testosterone treatment in vitro, by an AR-independent mechanism. Conclusion Taken together, these results suggest that Slit/Robo signaling represents a novel mechanism that regulates Leydig cell steroidogenesis. It may act in an autocrine/paracrine manner to mediate negative feedback by testosterone on its own synthesis.

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Transcription factor GCN4 for control of amino acid biosynthesis also regulates the expression of the gene for lipoamide dehydrogenase

Biochemical Journal ◽

10.1042/bj3400855 ◽

1999 ◽

Vol 340 (3) ◽

pp. 855-862 ◽

Cited By ~ 8

Author(s):

Zafar ZAMAN ◽

Susan B. BOWMAN ◽

Geoff D. KORNFELD ◽

Alistair J. P. BROWN ◽

Ian W. DAWES

Keyword(s):

Transcription Factor ◽

Amino Acid ◽

Amino Acid Biosynthesis ◽

Upstream Region ◽

Northern Analysis ◽

General Control ◽

Acid Biosynthesis ◽

Gene Encoding ◽

Lipoamide Dehydrogenase

The yeast LPD1 gene encoding lipoamide dehydrogenase is subject to the general control of amino acid biosynthesis mediated by the GCN4 transcription factor. This is striking in that it demonstrates that GCN4-mediated regulation extends much farther upstream than simply to the direct pathways for amino acid and purine biosynthesis. In yeast, lipoamide dehydrogenase functions in at least three multienzyme complexes: pyruvate dehydrogenase and 2-oxoglutarate dehydrogenase (which function in the entry of pyruvate into, and metabolism via, the citric acid cycle) and glycine decarboxylase. When wild-type cells were shifted from growth on amino acid-rich to amino acid-deficient medium, the expression of lipoamide dehydrogenase was induced approx. 2-fold. In a similar experiment no such induction was observed in isogenic gcn4 mutant cells. Northern analysis indicated that amino acid starvation affected levels of the LPD1 transcript. In the upstream region of LPD1 are three matches to the consensus for control mediated by GCN4. Directed mutagenesis of each site, and of all combinations of sites, suggests that only one site might be important for the general control response under the conditions tested. Gel-retardation analysis with GCN4 protein synthesized in vitro has indicated that GCN4 can bind in vitro to at least two of the consensus motifs.

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Comparison of cell types in the rat Leydig cell lineage after ethane dimethanesulfonate treatment

Reproduction ◽

10.1530/rep-12-0465 ◽

2013 ◽

Vol 145 (4) ◽

pp. 371-380 ◽

Cited By ~ 57

Author(s):

Jingjing Guo ◽

Hongyu Zhou ◽

Zhijian Su ◽

Bingbing Chen ◽

Guimin Wang ◽

...

Keyword(s):

Leydig Cell ◽

Leydig Cells ◽

Pubertal Development ◽

Cell Lineage ◽

Hydroxysteroid Dehydrogenase ◽

Mrna Levels ◽

Steroidogenic Enzymes ◽

Isolated Cells ◽

Adult Leydig Cells

The objective of this study was to purify cells in the Leydig cell lineage following regeneration after ethane dimethanesulfonate (EDS) treatment and compare their steroidogenic capacity. Regenerated progenitor (RPLCs), immature (RILCs), and adult Leydig cells (RALCs) were isolated from testes 21, 28 and 56 days after EDS treatment respectively. Production rates for androgens including androsterone and 5α-androstane-17β, 3α-diol (DIOL), testosterone and androstenedione were measured in RPLCs, RILCs and RALCs in media after 3-h in vitro culture with 100 ng/ml LH. Steady-state mRNA levels of steroidogenic enzymes and their activities were measured in freshly isolated cells. Compared to adult Leydig cells (ALCs) isolated from normal 90-day-old rat testes, which primarily produce testosterone (69.73%), RPLCs and RILCs primarily produced androsterone (70.21%) and DIOL (69.79%) respectively. Leydig cells isolated from testes 56 days post-EDS showed equivalent capacity of steroidogenesis to ALCs and primarily produced testosterone (72.90%). RPLCs had cholesterol side-chain cleavage enzyme, 3β-hydroxysteroid dehydrogenase 1 and 17α-hydroxylase but had almost no detectable 17β-hydroxysteroid dehydrogenase 3 and 11β-hydroxysteroid dehydrogenase 1 activities, while RILCs had increased 17β-hydroxysteroid dehydrogenase 3 and 11β-hydroxysteroid dehydrogenase 1 activities. Because RPLCs and RILCs had higher 5α-reductase 1 and 3α-hydroxysteroid dehydrogenase activities they produced mainly 5α-reduced androgens. Real-time PCR confirmed the similar trends for the expressions of these steroidogenic enzymes. In conclusion, the purified RPLCs, RILCs and RALCs are similar to those of their counterparts during rat pubertal development.

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MicroRNA-193b Controls Adiponectin Production in Human White Adipose Tissue

The Journal of Clinical Endocrinology & Metabolism ◽

10.1210/jc.2015-1530 ◽

2015 ◽

Vol 100 (8) ◽

pp. E1084-E1088 ◽

Cited By ~ 22

Author(s):

Yasmina Belarbi ◽

Niklas Mejhert ◽

Silvia Lorente-Cebrián ◽

Ingrid Dahlman ◽

Peter Arner ◽

...

Keyword(s):

Gene Expression ◽

Transcription Factor ◽

Adipose Tissue ◽

Nuclear Receptor ◽

White Adipose Tissue ◽

Mrna Levels ◽

Model Assessment ◽

Human Adipocytes ◽

Interacting Protein ◽

Nuclear Transcription Factor

Context: MicroRNAs (miRNAs) are posttranscriptional regulators of gene expression. In white adipose tissue (WAT), recent studies suggest that miRNA levels are altered in various metabolic diseases, including obesity. Objective: The objective of the study was to determine whether adipocyte-expressed miRNAs altered by obesity can regulate adiponectin expression/secretion in fat cells. Design: Eleven miRNAs previously shown to be altered in obese human WAT were overexpressed in human in vitro-differentiated adipocytes followed by assessments of adiponectin levels in conditioned media. Setting: This was cohort study (n = 56) in an academic hospital. Patients: Subcutaneous WAT was obtained from nonobese and obese individuals. Interventions: There were no interventions in this study. Main Outcome Measure(s): Protein and mRNA levels of adiponectin were measured. Results: Of the 11 investigated miRNAs, three (miR-193b/-126/-26a) increased adiponectin secretion when overexpressed in human adipocytes. However, in human WAT only miR-193b expression correlated with adiponectin gene expression and homeostasis model assessment of insulin resistance. Moreover, quantitative PCR of miR-193b in both WAT and isolated adipocytes showed a significant association with serum adiponectin levels. Overexpression of miR-193b altered the gene expression of seven known adiponectin regulators. 3′-untranslated region reporter assays confirmed binding to cAMP-responsive element binding protein 5, nuclear receptor interacting protein 1, and nuclear transcription factor Yα. The effects of miR-193b on nuclear transcription factor Yα expression were confirmed at the protein level. Transfection with individual miRNA target protectors selective for nuclear transcription factor Yα and nuclear receptor interacting protein 1 abolished the stimulatory effect of miR-193b on adiponectin secretion. Conclusions: In human adipocytes, miR-193b controls adiponectin production via pathways involving nuclear transcription factor Yα and possibly nuclear receptor interacting protein 1.

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