Down-Regulation of TSH Subunit mRNA Levels by Thyroid Hormones in the European Eel

1997 ◽  
Vol 108 (2) ◽  
pp. 191-198 ◽  
Author(s):  
Bérengère Pradet-Balade ◽  
Monika Schmitz ◽  
Christian Salmon ◽  
Sylvie Dufour ◽  
Bruno Quérat
Keyword(s):  
Thyroid Hormones ◽  
European Eel ◽  
Mrna Levels ◽  
Down Regulation ◽  
Subunit Mrna

Regulation of α and thyrotrophin-β subunit mRNA levels by androgens in the female rat

1990 ◽  
Vol 5 (1) ◽  
pp. 1-6 ◽  
Author(s):  
J. A. O. Ahlquist ◽  
J. A. Franklyn ◽  
D. B. Ramsden ◽  
M. C. Sheppard
Keyword(s):  
Thyroid Hormones ◽  
Mrna Levels ◽  
Female Rat ◽  
Β Subunit ◽  
Similar Reduction ◽  
Subunit Mrna ◽  
Genes Encoding ◽  
The Common ◽  
Influence Gene Expression ◽  
Serum Tsh

ABSTRACT Thyroid and steroid hormones act by similar mechanisms to influence gene expression in the anterior pituitary gland. The genes encoding the common α and TSH-β glycoprotein subunits are known to be regulated by thyroid hormones; we report here the effects of androgen administration on levels of α and TSH-β mRNA in pituitary cytoplasm in the euthyroid and hypothyroid female rat. Dihydrotestosterone (DHT) suppressed both α and TSH-β mRNAs to levels lower than those found in untreated animals; a similar reduction was seen in hypothyroid animals treated with DHT. A biphasic response of TSH-β mRNA was seen following administration of tri-iodothyronine (T3) to hypothyroid rats, with early stimulation followed by later inhibition; these changes were also evident after administration of T3 to androgen-treated animals, although mRNA levels were again suppressed. The effects of testosterone were similar to those of DHT. In contrast to the changes in mRNA levels, androgen administration did not lead to significant alterations in serum TSH concentrations or pituitary TSH content. These results indicate that, like thyroid hormones, androgens suppress both α and TSH-β subunit mRNA levels in the female rat. Androgens, however, exert differential effects on TSH synthesis and release which contrast with those of thyroid hormones.

scholarly journals Heterogeneous increases of cytoplasmic calcium: distinct effects on down-regulation of cell surface sodium channels and sodium channel subunit mRNA levels

2001 ◽  
Vol 132 (7) ◽  
pp. 1455-1466 ◽  
Author(s):  
Seiji Shiraishi ◽  
Izumi Shibuya ◽  
Yasuhito Uezono ◽  
Hiroki Yokoo ◽  
Yumiko Toyohira ◽  
...  
Keyword(s):  
Cell Surface ◽  
Sodium Channel ◽  
Sodium Channels ◽  
Mrna Levels ◽  
Cytoplasmic Calcium ◽  
Down Regulation ◽  
Subunit Mrna

scholarly journals Down-Regulation of the Proteoglycan Decorin Fills in the Tumor-Promoting Phenotype of Ionizing Radiation-Induced Senescent Human Breast Stromal Fibroblasts

Cancers ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1987
Author(s):  
Eleni Mavrogonatou ◽  
Adamantia Papadopoulou ◽  
Asimina Fotopoulou ◽  
Stathis Tsimelis ◽  
Heba Bassiony ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Ionizing Radiation ◽  
Cancer Progression ◽  
Breast Cancer Cell Lines ◽  
Phenotypic Trait ◽  
Mrna Levels ◽  
Human Breast ◽  
Down Regulation ◽  
Stromal Fibroblasts ◽  
Poor Prognostic Factor

Down-regulation of the small leucine-rich proteoglycan decorin in the stroma is considered a poor prognostic factor for breast cancer progression. Ionizing radiation, an established treatment for breast cancer, provokes the premature senescence of the adjacent to the tumor stromal fibroblasts. Here, we showed that senescent human breast stromal fibroblasts are characterized by the down-regulation of decorin at the mRNA and protein level, as well as by its decreased deposition in the pericellular extracellular matrix in vitro. Senescence-associated decorin down-regulation is a long-lasting process rather than an immediate response to γ-irradiation. Growth factors were demonstrated to participate in an autocrine manner in decorin down-regulation, with bFGF and VEGF being the critical mediators of the phenomenon. Autophagy inhibition by chloroquine reduced decorin mRNA levels, while autophagy activation using the mTOR inhibitor rapamycin enhanced decorin transcription. Interestingly, the secretome from a series of both untreated and irradiated human breast cancer cell lines with different molecular profiles inhibited decorin expression in young and senescent stromal fibroblasts, which was annulled by SU5402, a bFGF and VEGF inhibitor. The novel phenotypic trait of senescent human breast stromal fibroblasts revealed here is added to their already described cancer-promoting role via the formation of a tumor-permissive environment.

Pulmonary Ferritin: Differential Effects of Hyperoxic Lung Injury on Subunit mRNA Levels

1997 ◽  
Vol 22 (5) ◽  
pp. 901-908 ◽  
Author(s):  
Timothy P Ryan ◽  
Raymond F Krzesicki ◽  
David P Blakeman ◽  
Jia En Chin ◽  
Robert L Griffin ◽  
...  
Keyword(s):  
Lung Injury ◽  
Mrna Levels ◽  
Differential Effects ◽  
Subunit Mrna ◽  
Hyperoxic Lung Injury

Effect of experimental hypercholesterolaemia on K+ channel α-subunit mRNA levels in rabbit hearts

2007 ◽  
Vol 562 (1-2) ◽  
pp. 130-131 ◽  
Author(s):  
Angelika Varga ◽  
Péter Bagossi ◽  
József Tözsér ◽  
Barna Peitl ◽  
Zoltán Szilvássy
Keyword(s):  
K Channel ◽  
Mrna Levels ◽  
Α Subunit ◽  
Subunit Mrna

A novel mechanism of Ha-ras oncogene action: regulation of fibronectin mRNA levels by a nuclear posttranscriptional event

1994 ◽  
Vol 14 (5) ◽  
pp. 3085-3093
Author(s):  
L A Chandler ◽  
C P Ehretsmann ◽  
S Bourgeois
Keyword(s):  
Posttranscriptional Regulation ◽  
Tail Length ◽  
Common Mechanism ◽  
Osteosarcoma Cell ◽  
Mrna Levels ◽  
Ras Oncogene ◽  
Down Regulation ◽  
Regulate Gene Expression ◽  
Protein Levels ◽  
Human Osteosarcoma Cell

Although loss of cell surface fibronectin (FN) is a hallmark of many oncogenically transformed cells, the mechanisms responsible for this phenomenon remain poorly understood. The present study utilized the nontumorigenic human osteosarcoma cell line TE-85 to investigate the effects of induced Ha-ras oncogene expression on FN biosynthesis. TE-85 cells were stably transfected with metallothionein-Ha-ras fusion genes, and the effects of metal-induced ras expression on FN biosynthesis were determined. Induction of the ras oncogene, but not proto-oncogene, was accompanied by a decrease in total FN mRNA and protein levels. Transfection experiments indicated that these oncogene effects were not due to reduced FN promoter activity, suggesting that a posttranscriptional mechanism was involved. The most common mechanism of posttranscriptional regulation affects cytoplasmic mRNA stability. However, in this study the down-regulation of FN was identified as a nuclear event. A component of the ras effect was due to a mechanism affecting accumulation of processed nuclear FN RNA. Mechanisms that would generate such an effect include altered RNA processing and altered stability of the processed message in the nucleus. There was no effect of ras on FN mRNA poly(A) tail length or site of polyadenylation. There was also no evidence for altered splicing at the ED-B domain of FN mRNA. This demonstration of nuclear posttranscriptional down-regulation of FN by the Ha-ras oncogene identifies a new level at which ras oncoproteins can regulate gene expression and thus contribute to development of the malignant phenotype.

Royal Jelly Reduces Melanin Synthesis Through Down-Regulation of Tyrosinase Expression

2011 ◽  
Vol 39 (06) ◽  
pp. 1253-1260 ◽  
Author(s):  
Sang Mi Han ◽  
Joo Hong Yeo ◽  
Yoon Hee Cho ◽  
Sok Cheon Pak
Keyword(s):  
Royal Jelly ◽  
Mrna Levels ◽  
Dependent Manner ◽  
Melanin Synthesis ◽  
Mrna Transcription ◽  
Down Regulation ◽  
Melanin Biosynthesis ◽  
Skin Whitening ◽  
Key Enzyme ◽  
Dose Dependent

For cosmetic reasons, the demand for effective and safe skin-whitening agents is high. Since the key enzyme in the melanin synthetic pathway is tyrosinase, many depigmenting agents in the treatment of hyperpigmentation act as tyrosinase inhibitors. In this study, we have investigated the hypo-pigmentary mechanism of royal jelly in a mouse melanocyte cell line, B16F1. Treatment of B16F1 cells with royal jelly markedly inhibited melanin biosynthesis in a dose-dependent manner. Decreased melanin content occurred through the decrease of tyrosinase activity. The mRNA levels of tyrosinase were also reduced by royal jelly. These results suggest that royal jelly reduces melanin synthesis by down-regulation of tyrosinase mRNA transcription and serves as a new candidate in the design of new skin-whitening or therapeutic agents.

Exercise increases the plasma membrane content of the Na+ -K+ pump and its mRNA in rat skeletal muscles

1996 ◽  
Vol 80 (2) ◽  
pp. 699-705 ◽  
Author(s):  
T. Tsakiridis ◽  
P. P. Wong ◽  
Z. Liu ◽  
C. D. Rodgers ◽  
M. Vranic ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Plasma Membrane ◽  
Skeletal Muscles ◽  
Plasma Membranes ◽  
Acute Exercise ◽  
Treadmill Running ◽  
Type I ◽  
Mrna Levels ◽  
Subunit Mrna ◽  
White Type

Muscle fibers adapt to ionic challenges of exercise by increasing the plasma membrane Na+-K+ pump activity. Chronic exercise training has been shown to increase the total amount of Na+-K+ pumps present in skeletal muscle. However, the mechanism of adaptation of the Na+-K+ pump to an acute bout of exercise has not been determined, and it is not known whether it involves alterations in the content of plasma membrane pump subunits. Here we examine the effect of 1 h of treadmill running (20 m/min, 10% grade) on the subcellular distribution and expression of Na+-K+ pump subunits in rat skeletal muscles. Red type I and IIa (red-I/IIa) and white type IIa and IIb (white-IIa/IIb) hindlimb muscles from resting and exercised female Sprague-Dawley rats were removed for subcellular fractionation. By homogenization and gradient centrifugation, crude membranes and purified plasma membranes were isolated and subjected to gel electrophoresis and immunoblotting by using pump subunit-specific antibodies. Furthermore, mRNA was isolated from specific red type I (red-I) and white type IIb (white-IIb) muscles and subjected to Northern blotting by using subunit-specific probes. In both red-I/IIa and white-IIa/IIb muscles, exercise significantly raised the plasma membrane content of the alpha1-subunit of the pump by 64 +/- 24 and 55 +/- 22%, respectively (P < 0.05), and elevated the alpha2-polypeptide by 43 +/- 22 and 94 +/- 39%, respectively (P < 0.05). No significant effect of exercise could be detected on the amount of these subunits in an internal membrane fraction or in total membranes. In addition, exercise significantly increased the alpha1-subunit mRNA in red-I muscle (by 50 +/- 7%; P < 0.05) and the beta2-subunit mRNA in white-IIb muscles (by 64 +/- 19%; P < 0.01), but the alpha2- and beta1-mRNA levels were unaffected in this time period. We conclude that increased presence of alpha1- and alpha2-polypeptides at the plasma membrane and subsequent elevation of the alpha1- and beta2-subunit mRNAs may be mechanisms by which acute exercise regulates the Na+-K+ pump of skeletal muscle.

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