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

The purpose of this investigation was to elucidate the biological significance of lysine11 and of the tripeptide sequence =Lys-Pro-Val-NH2 for the biological activity of alpha-melanocyte-stimulating hormone. To this end the in vitro melanotropic activities of twenty-four synthetic peptides related to the hormone were determined. Extension or reduction of the length of the lysine11 side chain results in a marked decrease of the melanotropic potency of the respective analogue. The C-terminal tripeptide (11--13), the tetrapeptide (10--13), and the pentapeptide (9--13) were found to be hormonally active in the same order of magnitude as the central hexapeptide (5--10). The following conclusion was drawn: alpha-MSH possesses (in contrast to ACTH) two message sequences (active sites), (i)-Glu-His-Phe-Arg-Trp-, and (ii)-Gly-Lys-Pro-Val-NH2 which are capable of independently triggering the hormone receptor responsible for melanin dispersion. Thus, despite the close structural similarity of the two hormones, alpha-MSH and ACTH appear to react with their respective target cell receptors by quite different chemical mechanisms, implying different receptor structures.
 ...
PMID:Hormone-receptor interactions. The message sequence of alpha-melanotropin: demonstration of two active sites. 21 33

The cerebral uptake of subcutaneously injected [3H]2-deoxy-D-glucose (2DG) in 16 brain regions was examined following 30 noncontingent random footshocks or the acute injection of saline, ACTH1-24 (0.5 microgram/g), ACTH/MSH4-10 (0.25 microgram/g), [D-Phe7]ACTH4-10 (0.25 microgram/g), [Met4SO2,D-Lys8,Phe9]ACTH4-9 (0.01 microgram/g), ALPHA-MSH (0.5 microgram/g), corticosterone (2.5 microgram/g) or lysine vasopressin (0.05 microgram/g). Footshock selectively decreased 2DG uptake in parietal cortex and brain stem, and increased that in the hypothalamus. Whole brain 2DG uptake was decreased by injection of saline or most of the hormones relative to uninjected animals, but this effect was probably peripheral since plasma glucose content was increased by the injections. The only regionally specific effect of the hormones was an increased 2DG uptake in olfactory bulb by saline, ACTH/MSH4-10 And corticosterone relative to uninjected animals. Since alpha-MSH had been reported previously to decrease blood flow (measured by antipyrene uptake) in all brain regions except occipital cortex [5,6], we directly compared antipyrene uptake with 2DG uptake in the same animals using a double-isotope procedure. The results revealed an increase in 2DG uptake relative to antipyrene in cortical regions relative to subcortical regions, contradicting earlier assumptions [19].
 ...
PMID:Mouse brain deoxyglucose uptake after footshock, ACTH analogs, alpha-MSH, corticosterone or lysine vasopressin. 21 66

mRNA that encodes the common peptide precursor for the hormones corticotropin and beta-lipotropin was purified from the neurointermediate lobe of bovine pituitaries, and double-stranded cDNA species synthesized from this template were cloned in Escherichia coli X1776 by inserting them into the Pst I endonuclease cleavage site of the pBR322 plasmid using poly(dG)poly(dC) homopolymeric extensions. Certain of the cloned cDNA inserts contain nucleotides corresponding to the complete amino acid sequence of bovine corticotropin and a coding sequence that corresponds to at least the first portion of bovine beta-lipotropin. The nucleotide sequences coding for corticotropin and beta-lipotropin are separated on the cDNA by a 6-base-pair sequence encoding lysine and arginine, indicating that the carboxyl terminus of corticotropin is connected on the precursor peptide with the amino terminus of beta-lipotropin by these two amino acids. In addition, the cloned cDNA insert is characterized by an unusually high C+G nucleotide base content as well as by a number of DNA sequence duplications.
 ...
PMID:Construction of bacterial plasmids that contain the nucleotide sequence for bovine corticotropin-beta-lipotropin precursor. 21 7

The hypothalamic pituitary adrenocortical function has been studied in 16 patients operated from pituitary tumors (13 adenomas; 3 craniopharyngiomas). Comparisons have been made between corticotropin and cortisol response to lysine vasopressin, insulin induced-hypoglycemia and metyrapone IV and per os. Among these different stimulating tests, insulin induced hypoglycemia and metyrapone per os seem to give the more accurate informations metyrapone per os being more convenient because harmless. Three different groups of patients have been distinguished : one without adrenocortical deficiency; one with a complete deficiency and a third group with a partial deficiency. Correlations have been studied between the degree of the adrenocortical deficiency, the volume of the tumor and the presence of the absence of other anterior pituitary dysfunctions.
 ...
PMID:[Study of the hypothalamo-pituitary adrenal function in 16 patients after surgery for pituitary tumor (author's transl)]. 21 1

The nucleotide sequence of a 1,091-base pair cloned cDNA insert encoding bovine corticotropin-beta-lipotropin precursor mRNA is reported. The corresponding amino acid sequence indicates that the precursor protein consists of repetitive units and includes a third melanotropin sequence in its cryptic portion. Pairs of lysine and arginine residues separate the component peptides of the precursor.
 ...
PMID:Nucleotide sequence of cloned cDNA for bovine corticotropin-beta-lipotropin precursor. 22 18

A cDNA fragment synthesized from mouse mRNA (ACTH/LPH mRNA) that codes for the precursor polypeptide containing corticotropin (ACTH), beta-lipotropin (LPH), and several other peptides has been cloned in bacteria. The mRNA was enriched for ACTH/LPH mRNA translational activity (to about 75%) prior to cDNA synthesis. It appears to contain about 1200 bases, of which approximately 450 bases are not translated. The cloned DNA fragment is complementary to the region of the mRNA coding for the protein fragment beta-LPH-(44--90); this contains all of the amino acids of [Met]-enkephalin (residues 61--65 of beta-LPH), most of the amino acids of beta-melanocyte-stimulating hormone, and all but the carboxy-terminal amino acid of beta-endorphin. Based on assignment of the amino acid sequence of mouse beta-LPH from the nucelic acid sequence, it appears that there is extensive homology of mouse beta-LPH with human and porcine beta-LPH. The data also establish the linkage between beta-melanocyte-stimulating hormone and beta-endorphin as a Lys-Arg sequence. It is hoped that this cloned DNA can be used as a probe to study the expression and structure of the ACTH/LPH gene.
 ...
PMID:Corticotropin and beta-endorphin: construction and analysis of recombinant DNA complementary to mRNA for the common precursor. 22 16

Male mice were given a single injection of either adrenocorticotropic hormone (ACTH) or lysine vasopressin immediately after a defeat in an encounter with an aggressive male mouse. The defeated mice were tested for submissiveness at either 24 hours, 48 hours, or 7 days after the initial encounter. Both hormone treatments increased future submissiveness, although the time courses of the effects were different: The effects of ACTH disappeared after 48 hours, whereas those of vasopressin persisted for 7 days. These results suggest that changes in peptide hormone levels following naturally stressful experiences can affect the memory of those experiences, as expressed in future adaptive responses.
 ...
PMID:ACTH and vasopressin treatments immediately after a defeat increase future submissiveness in male mice. 22 73

A major and several minor trichloroacetic acid (TCA) soluble, bioassayable melanotropic peptides, as well as bioreactive and immunoreactive alpha-MSH have been found in the hypothalamus, olfactory bulb and cerebral cortex of normal and hypophysectomized rats. By employing subcellular fractionation procedures it was demonstrated that alpha-MSH and the major TCA soluble melanotropic peptide (MMPB) were localized in synaptosomes and were released by hypoosmotic shock. The analysis of MMPB by electrophoretic and chromatographic procedures reveales that it is not ACTH4-10, ACTH1-10, ACTH1-24, NAcACTH1-10 or alpha-MSH. MMPB was found to cross-react with an antiserum specific for the Lys-Pro-Val NH2 sequence in alpha-MSH, indicating that this C-terminal sequence of alpha-MSH may be present in its structure. MMPB was also shown to differ electrophoretically from the two major TCA soluble melanotropic peptides found in the neurointermediate lobe of the pituitary. In view of their synaptosomal localizations MMPB and alpha-MSH may play a role in synaptic function in the nervous system.
 ...
PMID:Melanotropic peptides: presence in brain of normal and hypophysectomized rats, and subcellularly localized in synaptosomes. 22 37

Three 3-hr incubations of pars intermedia cells from 40 rat pituitaries with [35S]methionine, [3H]lysine, and [3H]leucine sufficed for the identification and chemical characterization of biosynthesized beta-lipotropin, gamma-lipotropin, and beta-endorphin. From the molecular weight, migration on polyacrylamide gels, and sequence Met5, Lys9, Leu14,17, rat beta-endorphin was shown to be identical to its sheep homologue and no trace of Leu5 beta-endorphin could be detected. Rat beta-lipotropin differs from that of sheep in its elution properties on CM-cellulose, and its sequence shows Leu2,10,14, Lys20. Rat gamma-lipotropin shows the same NH2-terminal sequence as beta-lipotropin and is again different from its sheep homologue. The identification of rat beta-lipotropin was confirmed by its selective cleavage into beta-endorphin after trypsin digestion of the citraconylated peptide, a property not observed with rat gamma-lipotropin.
 ...
PMID:In vitro biosynthesis and chemical characterization of beta-lipotropin, gamma-lipotropin, and beta-endorphin in rat pars intermedia. 27 17

Protein biosynthesis in neurointermediate lobes of mouse pituitaries was investigated using pulse and pulse-chase techniques with [3H]lysine. Electrophoretic analysis of lobe homogenates on acid-urea gels resolved 11 labeled products. One was a large protein which was rapidly synthesized during pulse-incubations and disappeared during chase incubations. Three of the products increased during chase incubations, suggesting a precursor-product mode of biosynthesis for these chasde peptides. One of these three products co-migrated with synthetic alpha-MSH and also corresponds to the major peak of mouse neurointermediate lobe MSH bioactivity and immunoactivity on electrophoretograms. Another case of these peptides has electrophoretic properties similar to those of ACTH.
 ...
PMID:Biosynthesis of MSH and related peptides in the pars intermedia of the mouse: a pulse-chase analysis. 44 80


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>