scholarly journals ACTH-Dependent Regulation of MicroRNA As Endogenous Modulators of Glucocorticoid Receptor Expression in the Adrenal Gland

Endocrinology ◽  
2012 ◽  
Vol 153 (1) ◽  
pp. 212-222 ◽  
Author(s):  
Anna Riester ◽  
Orna Issler ◽  
Ariadni Spyroglou ◽  
Sharon Haramati Rodrig ◽  
Alon Chen ◽  
...  
Keyword(s):  
Adrenal Gland ◽  
Glucocorticoid Receptor ◽  
Expression Pattern ◽  
Untranslated Region ◽  
Target Genes ◽  
Receptor Expression ◽  
Acth Stimulation ◽  
Steroid Synthesis ◽  
Expression Levels ◽  
Baseline Conditions

MicroRNA (miR) are a subset of small RNA molecules, which posttranscriptionally modulate target gene expression. Although miR have been demonstrated to impact a number of processes during development and tumorigenesis, little is known about the expression and the role of miR in the adrenal gland. Because tight regulation of steroid synthesis is crucial for maintaining homeostasis upon stressful stimuli, here, we determined the miR expression pattern in mouse adrenal glands under baseline conditions, as well as 10, 30, and 60 min upon ACTH stimulation, using miR microarray. Changes in miR expression levels detected by array analysis were confirmed by real-time PCR and further analyzed by bioinformatic tools to identify miR that putatively target genes involved in adrenal function. After selecting miR, with a significant change in their expression level upon ACTH stimulation, four of the predefined miR (miR-96, miR-101a, miR-142-3p, and miR-433) were found to putatively target the glucocorticoid receptor [nuclear receptor subfamily 3, group C, member 1 (Nr3c1)]. Nr3c1 expression levels were elevated 10 min after ACTH stimulation but decreased after 60 min in comparison with baseline conditions. Modified Nr3c1-3′-untranslated region constructs were further tested by in vitro luciferase assays. Thereby, we could confirm that miR96, miR101a, miR142-3p, and miR433 target the Nr3c1-3′-untranslated region and result in a 20–40% repression of it. Taken together, ACTH stimulation could be demonstrated to acutely influence adrenal miR expression pattern in vivo; thus, potentially modulating adrenal response to acute stressors.

Transcriptional transactivation functions localized to the glucocorticoid receptor N terminus are necessary for steroid induction of lymphocyte apoptosis

1992 ◽  
Vol 12 (2) ◽  
pp. 589-597
Author(s):  
E S Dieken ◽  
R L Miesfeld
Keyword(s):  
Transcriptional Regulation ◽  
Glucocorticoid Receptor ◽  
Target Genes ◽  
Dominant Negative ◽  
Receptor Expression ◽  
Transactivation Domain ◽  
Lymphocyte Apoptosis ◽  
Murine Cell Line ◽  
N Terminus ◽  
Simplex Virus

Genetic studies have suggested that transcriptional regulation of specific target genes (by either induction or repression) is the molecular basis of glucocorticoid-mediated lymphocyte apoptosis. To examine the role of transcriptional regulation more directly, we developed a complementation assay utilizing stable transfection of wild-type (wt) and mutant (nti) glucocorticoid receptor (GR) cDNA constructs into a GR-deficient S49 murine cell line (7r). Our data confirm that the level of functional GR is rate limiting for S49 apoptosis and moreover that the GR amino terminus (N terminus), which as been deleted from the nti GR, is absolutely required for complementation in this system. Surprisingly, we found that at physiological levels of receptor, expression of the nti GR in cells containing wt GR results in enhanced dexamethasone sensitivity rather than a dominant negative phenotype. One interpretation of these data is that DNA binding by wt-nti heterodimers may be functionally similar to that of wt-wt homodimers, indicating that GRE occupancy by at least one transactivation domain may be sufficient to induce the hormonal response. To determine whether acidic activating sequences such as those localized to the GR N terminus are important in the induction of lymphocyte apoptosis, we tested the activity of a chimeric receptor in which we replaced the entire GR N terminus with sequences from the herpes simplex virus VP16 protein. Our results demonstrate that 7r cells expressing VP-GR fusions are indeed steroid sensitive, strongly supporting the idea that S49 apoptosis is dependent on transcriptional regulation of specific genes which respond to acidic activating domains, implying that induction, rather than repression, may be the critical initiating event.

Glucocorticoid Receptor Expression Correlates with Clinical Outcome in Myeloma Patients Treated with Glucocorticoid-Containing Regimens.

Blood ◽  
2008 ◽  
Vol 112 (11) ◽  
pp. 1700-1700 ◽  
Author(s):  
Shuo Ma ◽  
Fenghuang Zhan ◽  
Chunguang Ma ◽  
Michael Tessel ◽  
Lijun Zhang ◽  
...  
Keyword(s):  
Clinical Outcome ◽  
Glucocorticoid Receptor ◽  
Small Sample ◽  
Receptor Expression ◽  
Expression Level ◽  
Pcr Analysis ◽  
Clear Correlation ◽  
Newly Diagnosed ◽  
Expression Levels ◽  
Low Levels

Abstract Glucocorticoid (GC) is an effective anti-myeloma agent by directly inducing apoptosis and growth inhibition in myeloma cells. The anti-myeloma action of GC is mediated by its intracellular receptor, the glucocorticoid receptor (GR). The response to GC is variable among myeloma patients and resistance to glucocorticoid treatment develops almost invariably. The mechanism regulating glucocorticoid-sensitivity in not well understood, although it has been hypothesized that the regulation might occur at both the receptor (GR) and post-receptor level. In MM.1 myeloma cell lines, we observed significant down-regulation of GR expression as the cells develop GC-resistance, suggesting that GR expression level is an important determinant of GC-response. Here we present evidence that GR expression level directly correlates with the clinical outcome in myeloma patients who were treated with GC-containing regimens. First, using a quantitative real-time PCR analysis, we performed a retrospective analysis of GR gene expression on bone marrow plasma cell samples from 35 patients with newly diagnosed myeloma who were then treated on the ECOG study E1A00. This is a phase 3 trial which randomized patients to dexamethasone (dex) alone vs. dex in combination with thalidomide. Pre-treatment expression levels of GR-alpha, GR-beta and GR-P splicing isoforms were measured for 35 patients, of whom, 10 had post-treatment samples available. Interestingly, a large variation of the GR expression levels was observed across the patient samples, with the GR-alpha being the predominant isoform. However, a clear correlation between GR expression and treatment response was not seen, likely due to the small sample size. To access a larger patient pool, we retrospectively analyzed the GR expression levels using the cDNA microarray data from the Arkansas group on 351 newly diagnosed myeloma patients treated with Total Therapy 2, of which dexamethasone was an essential component throughout the treatment course. Of the 351 patients, both event-free (EFS) and overall survivals (OS) were compared between 49 patients (14%) with low levels of GR expression and the rest (86%) with high levels of GR expression. Strikingly, the cases with low levels of GR expression were associated with statistically significantly worse EFS and OS compared to those with high levels of GR expression, with the 5-year EFS of 20% vs. 52% and OS of 34% vs. 68%, P < 0.01. In summary, we have shown for the first time that the baseline level of glucocorticoid receptor expression in newly diagnosed myeloma patients predicts their clinical response to GC-containing regimen and the overall clinical outcome.

scholarly journals Expression Pattern of a Homeotic Gene, HOXA5, in Normal Breast and in Breast Tumors

2006 ◽  
Vol 28 (5-6) ◽  
pp. 305-313
Author(s):  
Gregory S. Henderson ◽  
Paul J. van Diest ◽  
Horst Burger ◽  
Jose Russo ◽  
Venu Raman
Keyword(s):  
Breast Cancer ◽  
Expression Pattern ◽  
Breast Tumors ◽  
Normal Breast ◽  
Receptor Expression ◽  
Homeotic Genes ◽  
Breast Carcinomas ◽  
Expression Levels ◽  
Egfr Expression ◽  
Breast Tissues

Introduction: Homeotic (HOX) gene products are now known to be functionally associated with breast cancer biogenesis. Recent evidence has indicated that HOXA5 regulates both p53 and progesterone receptor expression levels in breast cancer cells. In addition, HOXA5 has been shown to interact and regulate the activity of another protein referred to as Twist. As homeotic genes play a pivotal role in development, we sought to decipher the expression pattern in both normal breast tissues and in breast carcinomas. Methods: RT-PCR and immunohistochemistry were performed, to assay the levels of HOXA5 expression, on a panel of normal breast tissue and its corresponding primary breast tumors. Results and Conclusions: We show that HOXA5 expression was maintained at stable levels at different reproductive stages of a woman's life, except during lactation. This evidence indicates that HOXA5 may play a role in maintaining the differentiated state within the breast epithelium. However, nearly 70% of all breast carcinomas had decreased HOXA5 protein levels as compared to normal breast tissues. In addition, we demonstrate that HOXA5 protein expression levels in breast carcinomas inversely co-relates with Epidermal Growth Factor Receptor (EGFR) expression. Furthermore, we found that the survival rate amongst the different low levels of HOXA5 expressing breast tumors was not significant, indicative of an early tumorigenesis process in the absence of innate levels of HOXA5 in normal breast cells.

scholarly journals Transcriptional transactivation functions localized to the glucocorticoid receptor N terminus are necessary for steroid induction of lymphocyte apoptosis.

1992 ◽  
Vol 12 (2) ◽  
pp. 589-597 ◽  
Author(s):  
E S Dieken ◽  
R L Miesfeld
Keyword(s):  
Transcriptional Regulation ◽  
Glucocorticoid Receptor ◽  
Target Genes ◽  
Dominant Negative ◽  
Receptor Expression ◽  
Transactivation Domain ◽  
Lymphocyte Apoptosis ◽  
Murine Cell Line ◽  
N Terminus ◽  
Simplex Virus

Genetic studies have suggested that transcriptional regulation of specific target genes (by either induction or repression) is the molecular basis of glucocorticoid-mediated lymphocyte apoptosis. To examine the role of transcriptional regulation more directly, we developed a complementation assay utilizing stable transfection of wild-type (wt) and mutant (nti) glucocorticoid receptor (GR) cDNA constructs into a GR-deficient S49 murine cell line (7r). Our data confirm that the level of functional GR is rate limiting for S49 apoptosis and moreover that the GR amino terminus (N terminus), which as been deleted from the nti GR, is absolutely required for complementation in this system. Surprisingly, we found that at physiological levels of receptor, expression of the nti GR in cells containing wt GR results in enhanced dexamethasone sensitivity rather than a dominant negative phenotype. One interpretation of these data is that DNA binding by wt-nti heterodimers may be functionally similar to that of wt-wt homodimers, indicating that GRE occupancy by at least one transactivation domain may be sufficient to induce the hormonal response. To determine whether acidic activating sequences such as those localized to the GR N terminus are important in the induction of lymphocyte apoptosis, we tested the activity of a chimeric receptor in which we replaced the entire GR N terminus with sequences from the herpes simplex virus VP16 protein. Our results demonstrate that 7r cells expressing VP-GR fusions are indeed steroid sensitive, strongly supporting the idea that S49 apoptosis is dependent on transcriptional regulation of specific genes which respond to acidic activating domains, implying that induction, rather than repression, may be the critical initiating event.

Vitamin D decreasesin vitroglucocorticoid sensitivity via down regulation of glucocorticoid receptor expression

2015 ◽  
Author(s):  
Narjes Nasiri Ansari ◽  
Eliana Spilioti ◽  
Vasiliki Kalotychou ◽  
Geena Dalagiorgou ◽  
Paraskevi Moutsatsou ◽  
...  
Keyword(s):  
Vitamin D ◽  
Glucocorticoid Receptor ◽  
Receptor Expression ◽  
Down Regulation

Decreased glucocorticoid receptor expression during critical illness

2019 ◽  
Vol 49 (4) ◽  
pp. e13073 ◽  
Author(s):  
Alice G. Vassiliou ◽  
Georgios Floros ◽  
Edison Jahaj ◽  
Georgios Stamogiannos ◽  
Sofianna Gennimata ◽  
...  
Keyword(s):  
Critical Illness ◽  
Glucocorticoid Receptor ◽  
Receptor Expression

scholarly journals Analysis of miRNAs Targeted Storage Regulatory Genes during Soybean Seed Development Based on Transcriptome Sequencing

Genes ◽  
2019 ◽  
Vol 10 (6) ◽  
pp. 408 ◽  
Author(s):  
Jing-Yao Yu ◽  
Zhan-Guo Zhang ◽  
Shi-Yu Huang ◽  
Xue Han ◽  
Xin-Yu Wang ◽  
...  
Keyword(s):  
Expression Pattern ◽  
Seed Development ◽  
Small Rna ◽  
Target Genes ◽  
Soybean Seed ◽  
Regulatory Genes ◽  
Small Rna Sequencing ◽  
Grain Development ◽  
Regulatory Relationship ◽  
Novel Mirna

Soybeans are an important cash crop and are widely used as a source of vegetable protein and edible oil. MicroRNAs (miRNA) are endogenous small RNA that play an important regulatory role in the evolutionarily conserved system of gene expression. In this study, we selected four lines with extreme phenotypes, as well as high or low protein and oil content, from the chromosome segment substitution line (CSSL) constructed from suinong (SN14) and ZYD00006, and planted and sampled at three stages of grain development for small RNA sequencing and expression analysis. The sequencing results revealed the expression pattern of miRNA in the materials, and predicted miRNA-targeted regulatory genes, including 1967 pairs of corresponding relationships between known-miRNA and their target genes, as well as 597 pairs of corresponding relationships between novel-miRNA and their target genes. After screening and annotating genes that were targeted for regulation, five specific genes were identified to be differentially expressed during seed development and subsequently analyzed for their regulatory relationship with miRNAs. The expression pattern of the targeted gene was verified by Real-time Quantitative PCR (RT-qPCR). Our research provides more information about the miRNA regulatory network in soybeans and further identifies useful genes that regulate storage during soy grain development, providing a theoretical basis for the regulation of soybean quality traits.

Sign in / Sign up

Export Citation Format

Share Document