Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P56851 (epididymal)
 11,273 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The rat S14 gene encodes a protein of unknown function and has an amino acid sequence unrelated to any published sequences. Expression of mRNA S14 and lipogenesis in liver, fat, and mammary gland are regulated coordinately by dietary and hormonal stimuli, suggesting that the S14 protein may be associated with lipogenesis. Antisera to synthetic peptides corresponding to portions of the deduced amino acid sequence of the protein were used to identify the protein and to compare its regulation with that of mRNA S14. Antisera specifically recognized the in vitro translation product of mRNA S14 as defined by its migration on two-dimensional gel electrophoresis. A product of identical Mr was identified on Western blots of liver homogenates from hyperthyroid, carbohydrate-fed rats. Subcellular fractionation showed that S14 protein is primarily cytosolic. The protein was detectable in tissues with abundant S14 gene expression, including hyperthyroid liver and epididymal fat and hypothyroid brown adipose tissue, whereas it was undetectable in hypothyroid liver and euthyroid kidney, testis, and spleen. Diurnal variation in hepatic mRNA S14 correlated with comparable changes in levels of the protein. Surprisingly, no S14 protein was observed in the livers of chronically (3 week) hypothyroid rats treated with triiodothyronine (T3) until 12 h had elapsed, despite attainment of maximal levels of mRNA S14 within 4 h. Rapid appearance of protein after T3 treatment was observed in both euthyroid and short term (4 day) hypothyroid rats, suggesting that long-term hypothyroidism is associated with a defect in the translational efficiency of mRNA S14.
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PMID:Identification of rat S14 protein and comparison of its regulation with that of mRNA S14 employing synthetic peptide antisera. 258 93

In liver, thyroid hormone rapidly induces S14 mRNA, which encodes a small acidic protein. This sequence is abundantly expressed only in lipogenic tissues and is thought to have some function in fat metabolism. In the euthyroid rat, we measured 20-fold higher levels of S14 mRNA in interscapular brown adipose tissue than liver. Furthermore, whereas in liver or epididymal fat, hypothyroidism resulted in an 80% fall in S14 mRNA, in brown fat the level of this sequence increased a further 3-fold. In all three tissues, the expression of S14 mRNA correlated well with lipogenesis, as assessed by 3H2O incorporation. Physiological activation of brown fat by chronic cold exposure or cafeteria feeding increased the concentration of S14 mRNA in this tissue and again this was accompanied by a greater rate of fatty acid synthesis. Overall, in liver and white and brown adipose tissue, S14 mRNA and lipogenesis were well correlated and strongly suggest a function of the S14 protein related to fat synthesis. These studies suggest that the S14 protein and lipogenesis may be important for thyroid hormone-induced and brown adipose tissue thermogenesis and that stimulation of these functions in hypothyroid brown fat is a consequence of decreased thyroid hormone-induced thermogenesis elsewhere.
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PMID:Stimulation of S14 mRNA and lipogenesis in brown fat by hypothyroidism, cold exposure, and cafeteria feeding: evidence supporting a general role for S14 in lipogenesis and lipogenesis in the maintenance of thermogenesis. 347 52

We recently reported that T3 and the high carbohydrate lipogenic diet elicit a brisk and marked increase in the rat liver mRNA coding for the cytosolic protein Spot 14 (17,010 mol wt; 4.9 pI). By means of a hybridization assay, we have shown that the response of hepatic mRNAS14 to T3 and dietary manipulation is analogous to the response of many hepatic lipogenic enzymes. We extend our previous studies by examining mRNAS14 expression and regulation in other lipogenic and nonlipogenic tissues. The relative levels of mRNAS14 expression in three fat depots (epididymal, retroperitoneal, and brown fat) and lactating mammary gland are 10- and 4-fold higher, respectively, than that in euthyroid male liver. Expression of mRNAS14 in liver, epididymal fat, and mammary gland is augmented by T3, whereas feeding a lipogenic diet augments mRNAS14 in liver and fat only. In contrast, the relative levels of mRNAS14 in various nonlipogenic tissues (brain, heart, kidney, lung, spleen, testes, and pituitary) are 7% that in liver or less. Neither diet nor thyroid status influenced mRNAS14 levels in the nonlipogenic tissues. We also found that hepatic mRNAS14 in the 15-day-old rat is expressed at 0.3% of the adult (2-month) hepatic level and increases 186-fold from 15 to 30 days of age. We speculate that low levels of mRNAS14 in neonatal rat liver may be due to high fat in the milk diet. The presence of high basal levels of mRNAS14 in lipogenic tissues and its regulation by T3 and diet suggest that the Spot 14 protein may play an important role in some aspect of synthesis, metabolism, transport, or storage of lipid used in energy production. Further, our results emphasize that the presence of T3 receptors in a tissue is not sufficient to confer T3 regulation of mRNAS14 expression. Additional tissue-specific factors are required for the regulation of the Spot 14 gene.
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PMID:High basal expression and 3,5,3'-triiodothyronine regulation of messenger ribonucleic acid S14 in lipogenic tissues. 406 33