scholarly journals Pituitary transcription factor Prop-1 stimulates porcine pituitary glycoprotein hormone α subunit gene expression

2006 ◽  
Vol 37 (2) ◽  
pp. 341-352 ◽  
Author(s):  
Takanobu Sato ◽  
Kousuke Kitahara ◽  
Takao Susa ◽  
Takako Kato ◽  
Yukio Kato

Recently, we have reported that a Prophet of Pit-1 homeodomain factor, Prop-1, is a novel transcription factor for the porcine follicle-stimulating hormone β subunit (FSHβ) gene. This study subsequently aimed to examine the role of Prop-1 in the gene expression of two other porcine gonadotropin subunits, pituitary glycoprotein hormone α subunit (αGSU), and luteinizing hormone β subunit (LHβ). A series of deletion mutants of the porcine αGSU (up to −1059 bp) and LHβ (up to −1277 bp) promoters were constructed in the reporter vector, fused with the secreted alkaline phosphatase gene (pSEAP2-Basic). Transient transfection studies using GH3 cells were carried out to estimate the activation of the porcine αGSU and LHβ promoters by Prop-1, which was found to activate the αGSU promoter of −1059/+12 bp up to 11.7-fold but not the LHβ promoter. Electrophoretic mobility shift assay and DNase I footprinting analysis revealed that Prop-1 binds to six positions, −1038/−1026, −942/−928, −495/−479, −338/−326, −153/−146, and −131/−124 bp, that comprise the A/T cluster. Oligonucleotides of six Prop-1 binding sites were directly connected to the minimum promoter of αGSU, fused in the pSEAP2-Basic vector, followed by transfecting GH3 cells to determine the cis-acting activity. Finally, we concluded that at least five Prop-1 binding sites are the cis-acting elements for αGSU gene expression. The present results revealed a notable feature of the proximal region, where three Prop-1-binding sites are close to and/or overlap the pituitary glycoprotein hormone basal element, GATA-binding element, and junctional regulatory element. To our knowledge, this is the first demonstration of the role of Prop-1 in the regulation of αGSU gene expression. These results, taken together with our previous finding that Prop-1 is a transcription factor for FSHβ gene, confirm that Prop-1 modulates the synthesis of FSH at the transcriptional level. On the other hand, the defects of Prop-1 are known to cause dwarfism and combined pituitary hormone deficiency accompanying hypogonadism. Accordingly, the present observations provide a novel view to understand the hypogonadism caused by Prop-1 defects at the molecular level through the regulatory mechanism of αGSU and FSHβ gene expressions.

1993 ◽  
Vol 138 (2) ◽  
pp. 307-313 ◽  
Author(s):  
K. Shibayama ◽  
Y. Ohyama ◽  
M. Ono ◽  
S. Furudate

ABSTRACT The rdw rat (gene symbol: rdw) with hereditary dwarfism has been shown immunohistochemically to have subnormal numbers not only of GH- but also of prolactin- and thyrotrophin-positive cells. To characterize the dwarfism of this strain, the expression of pituitary hormone mRNAs was examined by Northern hybridization. The pituitary gland in the rdw rat expressed 30–100 times less GH and prolactin mRNAs than normal controls, whereas mRNAs for pro-opiomelanocortin and the α subunit of rat glycoprotein hormone revealed a significant increase. There was a non-significant difference in rat LH-β subunit and FSH-β subunit between normal and rdw rats. The suppressed expression of a pituitary-specific transcription factor, Pit-1, is considered to cause hereditary dwarfism in mouse strains Snell and Jackson, whose phenotypes resemble those of the rdw rat. In this study, however, no difference in mRNA expression for Pit-1 was found between rdw rats and controls. This work indicates that the rdw rat may not have the same genotype as the phenotypically similar dwarf mice, Snell, Jackson and Ames. Journal of Endocrinology (1993) 138, 307–313


2001 ◽  
Vol 7 (2) ◽  
pp. 187-200 ◽  
Author(s):  
TAE HO LEE ◽  
JERRY PELLETIER

The Wilms’ tumor suppressor gene, wt1, encodes a zinc finger transcription factor that can regulate gene expression. It plays an essential role in tumorigenesis, kidney differentiation, and urogenital development. To identify WT1 downstream targets, gene expression profiling was conducted using a cDNA array hybridization approach. We confirm herein that the human vitamin D receptor (VDR), a ligand-activated transcription factor, is a WT1 downstream target. Nuclear run on experiments demonstrated that the effect of WT1 on VDR expression is at the transcriptional level. Transient transfection assays, deletion mutagenesis, electrophoretic mobility shift assays, and chromatin immunoprecipitation assays suggest that, although WT1 is presented with a possibility of three binding sites within the VDR promoter, activation of the human VDR gene appears to occur through a single site. This site differs from a previously identified WT1-responsive site in the murine VDR promoter (Maurer U, Jehan F, Englert C, Hübinger G, Weidmann E, DeLucas HF, and Bergmann L. J Biol Chem 276: 3727–3732, 2001). We also show that the products of a Denys-Drash syndrome allele of wt1 inhibit WT1-mediated transactivation of the human VDR promoter. Our results indicate that the human VDR gene is a downstream target of WT1 and may be regulated differently than its murine counterpart.


2019 ◽  
Vol 116 (20) ◽  
pp. 9893-9902 ◽  
Author(s):  
Christopher M. Uyehara ◽  
Daniel J. McKay

The ecdysone pathway was among the first experimental systems employed to study the impact of steroid hormones on the genome. In Drosophila and other insects, ecdysone coordinates developmental transitions, including wholesale transformation of the larva into the adult during metamorphosis. Like other hormones, ecdysone controls gene expression through a nuclear receptor, which functions as a ligand-dependent transcription factor. Although it is clear that ecdysone elicits distinct transcriptional responses within its different target tissues, the role of its receptor, EcR, in regulating target gene expression is incompletely understood. In particular, EcR initiates a cascade of transcription factor expression in response to ecdysone, making it unclear which ecdysone-responsive genes are direct EcR targets. Here, we use the larval-to-prepupal transition of developing wings to examine the role of EcR in gene regulation. Genome-wide DNA binding profiles reveal that EcR exhibits widespread binding across the genome, including at many canonical ecdysone response genes. However, the majority of its binding sites reside at genes with wing-specific functions. We also find that EcR binding is temporally dynamic, with thousands of binding sites changing over time. RNA-seq reveals that EcR acts as both a temporal gate to block precocious entry to the next developmental stage as well as a temporal trigger to promote the subsequent program. Finally, transgenic reporter analysis indicates that EcR regulates not only temporal changes in target enhancer activity but also spatial patterns. Together, these studies define EcR as a multipurpose, direct regulator of gene expression, greatly expanding its role in coordinating developmental transitions.


2019 ◽  
Author(s):  
Christopher M. Uyehara ◽  
Daniel J. McKay

ABSTRACTThe ecdysone pathway was amongst the first experimental systems employed to study the impact of steroid hormones on the genome. In Drosophila and other insects, ecdysone coordinates developmental transitions, including wholesale transformation of the larva into the adult during metamorphosis. Like other hormones, ecdysone controls gene expression through a nuclear receptor, which functions as a ligand-dependent transcription factor. Although it is clear that ecdysone elicits distinct transcriptional responses within its different target tissues, the role of its receptor, EcR, in regulating target gene expression is incompletely understood. In particular, EcR initiates a cascade of transcription factor expression in response to ecdysone, making it unclear which ecdysone-responsive genes are direct EcR targets. Here, we use the larval-to-prepupal transition of developing wings to examine the role of EcR in gene regulation. Genome-wide DNA binding profiles reveal that EcR exhibits widespread binding across the genome, including at many canonical ecdysone-response genes. However, the majority of its binding sites reside at genes with wing-specific functions. We also find that EcR binding is temporally dynamic, with thousands of binding sites changing over time. RNA-seq reveals that EcR acts as both a temporal gate to block precocious entry to the next developmental stage as well as a temporal trigger to promote the subsequent program. Finally, transgenic reporter analysis indicates that EcR regulates not only temporal changes in target enhancer activity but also spatial patterns. Together, these studies define EcR as a multipurpose, direct regulator of gene expression, greatly expanding its role in coordinating developmental transitions.SIGNIFICANCENuclear receptors (NRs) are sequence-specific DNA binding proteins that act as intracellular receptors for small molecules such as hormones. Prior work has shown that NRs function as ligand-dependent switches that initiate a cascade of gene expression changes. The extent to which NRs function as direct regulators of downstream genes in these hierarchies remains incompletely understood. Here, we study the role of the NR EcR in metamorphosis of the Drosophila wing. We find that EcR directly regulates many genes at the top of the hierarchy as well as at downstream genes. Further, we find that EcR binds distinct sets of target genes at different developmental times. This work helps inform how hormones elicit tissue- and temporal-specific responses in target tissues.


Endocrinology ◽  
2007 ◽  
Vol 148 (7) ◽  
pp. 3468-3476 ◽  
Author(s):  
Kee K. Kim ◽  
Seok B. Song ◽  
Kwang I. Kang ◽  
Myungchull Rhee ◽  
Kyoon Eon Kim

Although there is evidence that the LIM homeodomain transcription factor, Lhx2, can stimulate transcription of the glycoprotein hormone α-subunit gene, the role of Lhx2 in regulating TSH β-subunit has not been established. In the present studies, the ability of Lhx2 to regulate transcription of the TSH β-subunit gene was examined. In the thyrotrope-derived TαT1 cell line, Lhx2 expression was found to be induced by treatment with either TRH or cAMP, consistent with the possibility that Lhx2 may play a role in mediating the ability of this signaling pathway to stimulate TSH gene expression. Transient, forced overexpression of Lhx2 stimulated activity of a TSH β-subunit reporter gene. Deletion studies provided evidence that the −177 to −79 region of the TSH β-subunit promoter was necessary for stimulation of reporter gene activity by Lhx2. A gel mobility shift assay provided the evidence that Lhx2 can bind to this region of DNA. DNase I footprinting studies demonstrated that two distinct regions of the TSHβ promoter, −118 to −108 and −86 to −68, are protected by Lhx2 from nuclease digestion. These regions contain repeats of the sequence, 5′-(G/T)CAAT(T/A)-3′. Mutation of this sequence, especially in the −86 to −68 region, substantially decreased Lhx2 responsiveness of the TSH β-subunit reporter gene. In addition, a DNA fragment containing the −177 to −79 region of the TSHβ promoter was found to confer Lhx2 responsiveness to a minimal promoter. These results provide multiple lines of evidence consistent with a role for Lhx2 in modulating expression of the TSH β-subunit gene.


2005 ◽  
Vol 79 (22) ◽  
pp. 14371-14382 ◽  
Author(s):  
Heesoon Chang ◽  
Dirk P. Dittmer ◽  
Shin-Young Chul ◽  
Youngkwon Hong ◽  
Jae U. Jung

ABSTRACT Kaposi's sarcoma-associated herpesvirus (KSHV) RTA transcription factor is recruited to its responsive elements through interaction with a Notch-mediated transcription factor, RBP-Jκ, indicating that RTA mimics cellular Notch signal transduction to activate viral lytic gene expression. To test whether cellular Notch signal transduction and RTA are functionally exchangeable for viral gene expression, human Notch intracellular (hNIC) domain that constitutively activates RBP-Jκ transcription factor activity was expressed in KSHV-infected primary effusion lymphoma BCBL1 cells (TRExBCBL1-hNIC) in a tetracycline-inducible manner. Gene expression profiling showed that like RTA, hNIC robustly induced expression of a number of viral genes, including viral interleukin 6 (vIL-6), K3, and K5. Unlike RTA, however, hNIC was not capable of evoking the full repertoire of lytic viral gene expression and thereby lytic replication. To further understand the role of Notch signal transduction in KSHV gene expression, vIL-6 growth factor and K5 immune modulator genes were selected for detailed analysis. Despite the presence of multiple RBP-Jκ binding sites, hNIC targeted the specific RBP-Jκ binding sites of vIL-6 and K5 promoter regions to regulate their gene expression. These results indicate that cellular Notch signal transduction not only is partially exchangeable with RTA in regard to activation of viral lytic gene expression but also provides a novel expression profile of KSHV growth and immune deregulatory genes that is likely different from that of RTA-independent standard latency program as well as RTA-dependent lytic reproduction program.


2021 ◽  
Vol 80 (Suppl 1) ◽  
pp. 23.2-24
Author(s):  
Y. P. Tsao ◽  
F. Y. Tseng ◽  
C. W. Chao ◽  
M. H. Chen ◽  
S. T. Chen

Background:Systemic lupus erythematous (SLE) is a systemic autoimmune disease with diverse etiological factors. It was recognized that interferon (IFN) signature involved in the progress of SLE. NLRP12 (NOD-like receptor family (NLR) pyrin domain containing 12) is a pyrin containing NLR protein that we had linked its new biological function to the cross-regulation of Toll like receptor (TLRs) and Rig-I like receptor (RIG-I) pathways. NLPR12 acts as an innate immune check-point in regulating type I IFNs expression during TLRs and RIG-I activation. The importance of NLRP12 in lupus disease activity remained to be elucidated.Objectives:To clarify the role of NLRP12 in regulating the interferon signature.Methods:Peripheral blood mononuclear cells (PBMCs) were collected from SLE patients and healthy donors for analysis of NLRP12 and IFN-α gene expression by RT-QPCR. PBMCs were applied for Chromatin immuneprecipitation (ChIP) assay and electrical mobility shift assay (EMSA) to determine the putative transcription factor that regulates NLRP12 expression. An involvement of epigenetic regulation of NLRP12 expression in SLE patients was also analyzed. Bone marrow derived dendritic cells (BMDCs) were collected from wild type mouse and Nlrp12 knocked-out mice. Another CD14+ monocytes were isolated from 10 cases of lupus patients and 8 cases of healthy control, following by stimulating different type of nucleic acids, and IFN-α and IL-6 were measured with ELISA assay. CD14+ monocytes in lupus patients were also pre-treated with IFNAR2 antibody for further nucleic acid stimulation. Two mice models were applied for evaluation the role of Nlrp12: intraperitoneal injection of TMPD (2,6,10,14-tetramethylpentadecane, or pristane) in C57BL/6 mice and Faslpr mice. Both models were conducted with and without Nlrp12 knockout.Results:NLRP12 expression was significantly lower in PBMC isolated from SLE patients compared to healthy donors. The inverse correlation was observed in NLRP12 and IFNA gene expression as well as NLRP12 expression and amount of double-stranded DNA autoantibody in SLE patients. NLRP12 expression showed negative correlations with IFN-α treatment, as well as herpes simplex virus-1 (HSV-1) infection. Results from ChIP and EMSA analysis indicated a potential transcription factor 1 (TF-1) regulating NLRP12 promoter activity. TF-1 lead to transcriptional suppression of NLRP12 in SLE PBMC, and it was gradually induced after IFN treatment. Recruitment of TF-1 to NLRP12 promoter in SLE PBMC compared to the healthy PBMC was detected, and increased when treating with IFN. Human CD14+ monocytes collected from lupus and healthy control stimulating with different type of nucleic acids revealing significant increasing level of IFN-α and IL-6 in lupus patients. Among animal models, both pristine induced mice and Faslpr mice revealed increasing autoantibodies production and severity of glomerulonephritis in Nlrp12-/- group in comparison with Nlrp12+/+ ones, indicating the role of NLRP12 in maintaining positive interferon signature as well as disease activity.Conclusion:Expression level of NLRP1.2 has been demonstrated to be a biomarker of disease activity in SLE patients. The NLRP12 was involved in the interferon signature, which was also negatively regulated by TF-1. Both clinical samples and animal models revealed NLRP12 in maintaining the positive interferon signature, indicating the possible role of exacerbating factor for lupus disease activity.Disclosure of Interests:None declared


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Kulisara Marupanthorn ◽  
Chairat Tantrawatpan ◽  
Pakpoom Kheolamai ◽  
Duangrat Tantikanlayaporn ◽  
Sirikul Manochantr

AbstractMesenchymal stem cells (MSCs) are important in regenerative medicine because of their potential for multi-differentiation. Bone marrow, chorion and placenta have all been suggested as potential sources for clinical application. However, the osteogenic differentiation potential of MSCs derived from chorion or placenta is not very efficient. Bone morphogenetic protein-2 (BMP-2) plays an important role in bone development. Its effect on osteogenic augmentation has been addressed in several studies. Recent studies have also shown a relationship between miRNAs and osteogenesis. We hypothesized that miRNAs targeted to Runt-related transcription factor 2 (Runx-2), a major transcription factor of osteogenesis, are responsible for regulating the differentiation of MSCs into osteoblasts. This study examines the effect of BMP-2 on the osteogenic differentiation of MSCs isolated from chorion and placenta in comparison to bone marrow-derived MSCs and investigates the role of miRNAs in the osteogenic differentiation of MSCs from these sources. MSCs were isolated from human bone marrow, chorion and placenta. The osteogenic differentiation potential after BMP-2 treatment was examined using ALP staining, ALP activity assay, and osteogenic gene expression. Candidate miRNAs were selected and their expression levels during osteoblastic differentiation were examined using real-time RT-PCR. The role of these miRNAs in osteogenesis was investigated by transfection with specific miRNA inhibitors. The level of osteogenic differentiation was monitored after anti-miRNA treatment. MSCs isolated from chorion and placenta exhibited self-renewal capacity and multi-lineage differentiation potential similar to MSCs isolated from bone marrow. BMP-2 treated MSCs showed higher ALP levels and osteogenic gene expression compared to untreated MSCs. All investigated miRNAs (miR-31, miR-106a and miR148) were consistently downregulated during the process of osteogenic differentiation. After treatment with miRNA inhibitors, ALP activity and osteogenic gene expression increased over the time of osteogenic differentiation. BMP-2 has a positive effect on osteogenic differentiation of chorion- and placenta-derived MSCs. The inhibition of specific miRNAs enhanced the osteogenic differentiation capacity of various MSCs in culture and this strategy might be used to promote bone regeneration. However, further in vivo experiments are required to assess the validity of this approach.


2021 ◽  
Vol 12 (9) ◽  
Author(s):  
Xuexiu Zhang ◽  
Jianning Yao ◽  
Haoling Shi ◽  
Bing Gao ◽  
Haining Zhou ◽  
...  

AbstractCircular RNAs (circRNAs) have been reported to play crucial roles in the progression of various cancers, including colorectal cancer (CRC). SP1 (Sp1 transcription factor) is a well-recognized oncogene in CRC and is deemed to trigger the Wnt/β-catenin pathway. The present study was designed to investigate the role of circRNAs which shared the same pre-mRNA with SP1 in CRC cells. We identified that hsa_circ_0026628 (circ_0026628), a circular RNA that originated from SP1 pre-mRNA, was upregulated in CRC cells. Sanger sequencing and agarose gel electrophoresis verified the circular characteristic of circ_0026628. Functional assays including CCK-8, colony formation, transwell, immunofluorescence staining, and sphere formation assay revealed the function of circ_0026628. RNA pull-down and mass spectrometry disclosed the proteins interacting with circ_0026628. Mechanistic assays including RIP, RNA pull-down, CoIP, ChIP, and luciferase reporter assays demonstrated the interplays between molecules. The results depicted that circ_0026628 functioned as a contributor to CRC cell proliferation, migration, EMT, and stemness. Mechanistically, circ_0026628 served as the endogenous sponge of miR-346 and FUS to elevate SP1 expression at the post-transcriptional level, thus strengthening the interaction between SP1 and β-catenin to activate the Wnt/β-catenin pathway. In turn, the downstream gene of Wnt/β-catenin signaling, SOX2 (SRY-box transcription factor 2), transcriptionally activated SP1 and therefore boosted circ_0026628 level. On the whole, SOX2-induced circ_0026628 sponged miR-346 and recruited FUS protein to augment SP1, triggering the downstream Wnt/β-catenin pathway to facilitate CRC progression.


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