Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P01189 (beta-endorphin)
 21,003 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A radioimmunoassay has been developed for the N-terminal region of human pituitary pro-opiocortin (N-POC), the common precursor protein of ACTH and beta-LPH, using an antiserum which recognizes residues near the gamma-MSH region. The concentrations of greater than 300 ng/l of immunoreactive peptide were determined in unextracted human plasma, the relative molecular mass of the reacting fragments corresponding to a seventy-seven amino acid glycoprotein. The concentrations of immunoreactive N-POC peptides were correlated with those of ACTH in plasma obtained from patients with various disorders of the hypothalamic-pituitary-adrenal axis.
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PMID:Development of a radioimmunoassay for an amino-terminal peptide of pro-opiocortin containing the gamma-MSH region: measurement and characterization in human plasma. 627 26

gamma MSH-like, ACTH-like, and beta-endorphin-like immunoreactivities (gamma MSH-LI, ACTH-LI, and beta-endorphin-LI, respectively) were detected in water extracts of four human gastric antral mucosa. The concentrations of gamma MSH-LI, ACTH-LI, and beta-endorphin-LI in the boiling water extracts were 9.9 +/- 3.3, 6.2 +/- 1.8, and 3.9 +/- 1.3 ng/g (mean +/- SE), respectively. Gel exclusion chromatography on a Bio-Gel P-60 column showed that most ACTH-LI and beta-endorphin-LI were eluted at the elution positions of human ACTH and beta-endorphin, respectively. The major peak of gamma MSH-LI was eluted at the elution position of big gamma MSH-LI, but another peak was eluted at the elution position of small gamma MSH-LI, as in bovine intermediate pituitary. Concanavalin A-agarose affinity chromatography showed that 52% of gamma MSH-LI was specifically bound to the column, but only 8% of ACTH-LI and none of beta-endorphin-LI were specifically bound. These results suggest that there exists an ACTH/beta-lipotropin common precursor protein in human antral mucosa and that the processing of the precursor is accelerated as a bovine intermediate pituitary, indicating possible roles of these peptides in the function of the gastrointestinal tract.
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PMID:Presence of immunoreactive gamma-melanocyte-stimulating hormone, adrenocorticotropin, and beta-endorphin in human gastric antral mucosa. 627 2

The nucleotide sequence of cloned cDNA for preproenkephalin from bovine adrenal medulla indicates that the precursor protein contains four copies of Met-enkephalin and one copy each of Leu-enkephalin, Met-enkephalin-Arg6-Phe7 and Met-enkephalin-Arg6-Gly7-Leu8, a previously undetected opioid peptide. The enkephalin and extended enkephalin sequences are each bounded by paired basic amino acid residues. Preproenkephalin may represent a multi-hormone precursor, like the corticotropin-beta-lipotropin precursor.
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PMID:Cloning and sequence analysis of cDNA for bovine adrenal preproenkephalin. 627 59

gamma MSH, a putative hormone in the N-terminal region of the ACTH/beta-endorphin (beta-EP) precursor protein, was studied by RIA with an antiserum against gamma 3MSH in ACTH-producing mouse pituitary tumor cells, AtT-20/D16v. Serial dilution of the culture medium or the cell extract gave parallel lines to the standard curve in the RIA for gamma MSH. Rat median eminence extracts enhanced the release of gamma MSH-like immunoreactivity (gamma MSH-LI) concomitant with ACTH-like immunoreactivity (ACTH-LI) and beta-EP-like immunoreactivity (beta-EP-LI). Dexamethasone suppressed the release of gamma MSH-LI as well as ACTH-LI and beta-EP-LI. Gel exclusion chromatography of the culture medium and the cell extract has revealed that gamma MSH-LI consists of two peaks; one eluted near the elution position of beta-lipotropin and the other near the elution position of beta-EP. There was no peak corresponding to the elution position of synthetic gamma 3MSH. However, sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) has demonstrated that gamma MSH-LI migrated at five positions with molecular weights of 31K, 21-23K, 16-17K, 13-14K, and 3.8K, respectively. The 31K gamma MSH coincided with the migration position of 31K ACTH of 31K beta-EP, and 21-23K gamma MSH coincided with the position of 21-23K ACTH on SDS-PAGE. The 16-17K gamma MSH coincided with the mouse 16K fragment (reported by Eipper and Mains) of ACTH-beta-lipotropin precursor protein in the migration in SDS-PAGE and in immunoreactivity to anti-gamma MSH antiserum. [3H]Glucosamine was incorporated into 16K, 13K, and 3.8K gamma MSH. These results suggest that AtT-20/D16v cells produce gamma MSH-LIs with molecular weights of 31K, 21-23K, 16-17K, 13-14K, and 3.8K, and they are secreted concomitantly with ACTH-LI and beta-EP-LI.
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PMID:Characterization of gamma-melanotropin-like immunoreactivity and its secretion in an adrenocorticotropin-producing mouse pituitary tumor cell line. 628 79

The human and the bovine corticotropin (ACTH)-beta-lipotropin (LPH) precursor gene have been isolated and characterized. Both genes consist of three exons which are divided by two large introns at exactly the same positions. One of the introns is inserted within the segment transcribed into the 5'-untranslated region of the mRNA, and the other interrupts the protein-coding sequence near the signal peptide region. The largest exon encodes most of the protein sequence which includes the three repeated melanotropin (MSH) peptides and other biologically active peptides such as ACTH and beta-endorphin. Thus, there is no apparent correspondence between the repetitive structure of the precursor protein and the structural organization of its gene. Comparison of the nucleotide sequences of the human and the bovine gene reveals that three regions are highly conserved, i.e., the region extending from the signal peptide to gamma-MSH, the ACTH region and the beta-MSH/beta-endorphin region. This suggests that the peptide(s) in the amino-terminal region, including gamma-MSH, may be of physiological importance, as is the case for ACTH and beta-endorphin. The different biologically active component peptides of the ACTH-beta-LPH precursor, encoded by a single gene, seem to be involved in the defense mechanism of the living organism by acting coordinately in the central nervous system as well as in peripheral tissues. The identification of the mRNA encoding the ACTH-beta-LPH precursor in a human ectopic ACTH-producing tumor is also reported.
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PMID:Structural organization of the corticotropin-beta-lipotropin precursor gene. 630 21

Many lower vertebrates exhibit colour change in response to the background. A dual hormonal control of colour change by two antagonistic pituitary melanophorotropic hormones was first postulated in amphibia by Hogben and Slome. It is well established that the melanotropins alpha- and beta-MSH are responsible for pigment dispersion in the integumentary melanophore of lower vertebrates and that these molecules are derived from a common precursor protein, proopiocortin, by specific processing within the intermediate lobe. No evidence has been found for an antagonistic hormone in amphibia, although the existence of such a molecule in the pituitary gland of teleost fishes has long been recognized and was termed the melanophore-concentrating hormone by Enami. Early attempts to separate the two hormones proved unsuccessful. Recently, Baker and Ball re-invoked the dual hormone concept, and it has been suggested that a melanin-concentrating hormone (MCH) is synthesized in the hypothalamus of teleosts and stored and released by the neurohyphophysis. We have now isolated a novel peptide from the pituitary of the salmon (Oncorhynchus keta) possessing an antagonistic function to MSH, and we describe here its chemical and biological characteristics.
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PMID:Characterization of melanin-concentrating hormone in chum salmon pituitaries. 662 86

The content of met-enkephalin (met-EK)-like peptides in a crude extract from intact pulp of the rat markedly increased with tryptic digestion but not with carboxypeptidase B(CPase B) digestion, while the content of leu-enkephalin (leu-EK)-like peptides more markedly with CPase B- than with tryptic digestion. On the other hand, results by High Performance Liquid Chromatography (HPLC) showed that the contents of both met-EK-Arg-Phe and leu-EK in cavity formed pulp increased 6 times as much as those contents in intact pulp, while the met-EK content in cavity formed pulp increased 2 times as much as that in intact pulp. Furthermore, results by gel filtration of crude extract from intact pulp showed that one peak of met-EK-like immunoreactivity (met-EK-IR) appeared at position of approximately 30,000 of molecular weight and a broad peak of leu-EK-IR appeared at position of approximately 60,000 of molecular weight following tryptic digestion. From these results, it was suggested that noxious stimuli might cause activation of trypsin-like enzymes followed by processing from one precursor protein to met-EK-like peptides as well as from another to leu-EK-like peptides in the rat incisor pulps.
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PMID:A possible relationship between processing from precursor proteins to opioid peptides and noxious stimulation in the rat incisor pulp. 666 44

Enkephalins are pentapeptides with opioid activity which are found in a wide variety of tissues. Studies of enkephalin-containing peptides from the adrenal gland have established that the mature pentapeptides are derived by proteolytic processing of a precursor protein. We have shown that human adrenal medullary tumours contain mRNA which can be translated in vitro to yield a single major enkephalin precursor. The sequence of cloned cDNA shows that the preproenkephalin mRNA encodes four copies of met-enkephalin, two copies of met-enkephalin extended sequences and one copy of leu-enkephalin; each copy is flanked by paired basic amino acids which are presumably recognised by the processing protease. We have used the cloned human cDNA as a hybridisation probe to detect the corresponding mRNAs in rat adrenal gland and, in smaller amounts, in rat brain. We have been unable to detect in brain any other cross-hybridising mRNAs which might encode other putative precursor proteins.
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PMID:The structure and expression of the preproenkephalin gene. 676 48

This study was designed to determine whether pituitary glands contain an immunoreactive material which reacts with antisera to calcitonin (CT) and, if so, whether secretion of the material could be demonstrated. Testing 15 antisera to rat and human CT and using an immunoperoxidase method, we found 2 antisera to human CT which stained rat pituitaries and several which stained human pituitaries. Essentially all cells in the rat intermediate lobe and scattered cells in the rat and human anterior lobes showed staining, and staining was not entirely abolished by prior adsorption of antisera with rat or human CT. The 2 antisera which stained rat pituitaries showed cross-reactivity with several synthetic human CT fragments (1-18, 11-23 and 22-32) but not with ACTH-(1-39), ACTH-(1-24), beta-endorphin, alpha- or beta MSH, or bovine lipotropin. Crude extracts of pituitaries from 2 strains of young rats showed CT-like immunoreactivity which could be measured easily by RIA (0.2-0.3 ng/gland). In vivo, an antiserum which stained pituitaries and 1 which did not were compared using young rats made hypercalcemic (15-20 mg/dl) with iv Ca. In rats with thyroids, both antisera showed an increase in serum CT of more than 15-fold whether the pituitary was present or absent. In thyroidectomized rats, serum CT remained undetectable (less than 50 to 100 pg/ml) during hypercalcemia even if the pituitary was present. In vitro, rat pituitaries in a serum-free medium did not release measurable amounts of immunoreactive CT-like material even when medium contained high Ca (2.5 mM), high K (25 mM), or TRH (10(-6) M). Therefore, the findings agree with other reports of a CT-like material in the pituitary, but no secretion of the material could be demonstrated. We hypothesize that the material is not authentic CT but is, rather a related peptide sequence probably contained in the 31 K precursor protein of ACTH-beta-lipotropin.
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PMID:Calcitonin-like immunoreactivity in rat and human pituitary glands: histochemical, in vitro, and in vivo studies. 737 58

A new melanocyte-stimulating peptide has been isolated from acid extracts of frozen human pituitary glands by salt/ethanol fractionation, Sephadex G-75 gel filtration and DEAE- and cM-cellulose ion-exchange chromatography. The peptide is glycosylated, has an N-terminal tryptophan residue and an apparent mol.wt. of 16000 as estimated by sodium dodecyl sulphate/polyacrylamide-gel electrophoresis. Its amino acid analysis closely resembles residues Trp-105 to Gln-29 predicted for the common precursor protein of bovine corticotropin and beta-lipotropin by Nakanishi, Inoue, Kita, Nakamura, Chang, Cohen & Numa [(1979) Nature (London) 278, 423-427]. This fragment is expected to have melanotropin activity due to the tetrapeptide -His-Phe-Arg-Trp- (residues -51 to -48) of the predicted sequence of the common precursor. It was found to have a molar potency of 1 X 10(-5) relative to alpha-melanotropin in the frog skin bioassay. These characteristics are consistent with the isolated melanotropin peptide being a non-corticotropin, non-lipotropin peptide of the human common precursor protein of corticotropin and lipotropin. The peptide neither potentiates the adrenal weight-maintenance activity of corticotropin-(1-24)-tetracosapeptide when administered to hypophysectomized rats, nor stimulates release of non-esterified fatty acids from isolated rat epididymal cells. A second N-terminal-tryptophan glycopeptide was also isolated, which had an amino-acid composition similar to that predicted for the bovine common precursor protein, residues Trp-105 to Gly-35.
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PMID:Purification and characterization of a gamma-melanotropin precursor from frozen human pituitary glands. 747 89


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