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)

As a step for analysis of the transcriptional regulation of the adrenocorticotropin (ACTH) receptor gene, I have made an attempt to obtain a full length cDNA and determined the genomic organization of the mouse ACTH receptor. Using the 5'-RACE (rapid amplification of cDNA ends) method, a 374bp sequence upstream of the translation start codon ATG of the receptor was obtained. By comparison of the 374bp sequence with the 1.8kb genomic sequence within the phage clone, lambda mCTR8, containing the mouse ACTH receptor coding region as described previously, a 95bp sequence of the 5'-RACE-generated cDNA was found to locate from the position of -1 to -95 from the ATG, and a 113bp sequence of the 5'-RACE-generated cDNA was found in the genomic sequence approximately 1.6kb upstream of the ATG. Because of the absence of a 166bp sequence, -209 to -374, in lambda mCTR8, further screening of a mouse genomic library was performed. By analysis of two positive clones, a 109bp and a 57bp sequence, -266 to -374 and -209 to -265, respectively, were located approximately 6.0kb away from each other in the phage clones which were not overlapped with lambda mCTR8. The 3'non-coding region of the mouse ACTH receptor cDNA obtained by 3'-RACE method was contiguous to the coding region by comparing it with the 1.4kb genomic sequence downstream of the ATG. The polyadenylation signal AATAAA was located at the position of 1291 from the ATG. Taken together, the mouse ACTH receptor gene consists of at least 4 exons and three of the exons encoded 5'-untranslated sequences. Moreover, two mRNAs in the presence and absence of the 57bp putative exon 2 generated by alternative splicing were determined by reverse transcription/polymerase chain reaction between putative exon 1 and 4. Finally, the longest cDNA of this gene determined from this experiment was 1707bp while northern analysis revealed approximately 1.8kb mRNA in mouse adrenal gland. It awaits further investigation to clarify the significance of 5'-untranslated non-coding exons and alternative splicing in this receptor gene.
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PMID:[The genomic organization of the mouse adrenocorticotropin receptor]. 893 9

Although production of pro-opiomelanocortin (POMC) mRNA and POMC-derived peptides in extrapituitary tissues, including immune tissues, has been demonstrated, questions remain concerning the nature of POMC transcripts and peptide products. With regard to POMC gene expression in lymphocytes, the expression of full-length mRNA and POMC has been questioned. In the present report, we have tested for the existence of these molecules. Western blot analysis with an antibody against POMC-derived adrenocorticotropic hormone (ACTH) specifically identified identical immunoreactive (ir) species in both rat anterior pituitary (AP) and splenocyte cell extracts. The relative molecular weights were those expected for nonglycosylated ACTH, as well as its biosynthetic intermediate, and POMC. Mitogen stimulation of splenic mononuclear cells (MNC) enhanced the levels of these three molecular species. Primer extension analysis identified a band which migrated with a size equivalent to a full-length POMC transcript (approximately 816 nt) in both mitogen-stimulated MNC and AP mRNA. Macrophages produced POMC protein and mRNA among unstimulated splenocytes, while lymphocytes could be induced to produce POMC mRNA upon stimulation. 5' RACE-tailed PCR products were cloned and sequenced. A mRNA encoding all three POMC exons was identified in Concanavalin A (ConA)-stimulated MNC and was identical to that from the anterior pituitary. These results unequivocally demonstrate that mononuclear cells produce full-length POMC transcripts. Its regulation in lymphocytes is distinct from that in macrophages which constitutively produce POMC-derived peptides and mRNA. Also, the biosynthetic pathway of ACTH from POMC in splenic MNC stimulated with ConA appears to be identical to that in rat corticotrophs.
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PMID:Pro-opiomelanocortin gene expression and protein processing in rat mononuclear leukocytes. 930 27

A degenerate primer, specific for the opioid core sequence YGGFM, was used to clone and sequence proopiomelanocortin (POMC) cDNAs from the brain of the African lungfish, Protopterus annectens, and from the brain of the western spadefoot toad, Spea multiplicatus. In addition, the opioid-specific primer was used to clone and sequence a 3'RACE product corresponding to a portion of the open reading frame of S. multiplicatus proenkephalin. For both species, cDNA was made from a single brain and a degenerate opioid-specific primer provided a reliable probe for detecting opioid-related cDNAs. The African lungfish POMC cDNA was 1,168 nucleotides in length, and contained regions that are similar to tetrapod POMCs and fish POMCs. The African lungfish POMC encodes a tetrapod-like gamma-MSH sequence that is flanked by sets of paired basic amino acid proteolytic cleavage sites. The gamma-MSH region in ray-finned fish POMCs either has degenerate cleavage sites or is totally absent in some species. However, the African lungfish gamma-MSH sequence does contain a deletion which has not been observed in tetrapod gamma-MSH sequences. The beta-endorphin region of lungfish POMC has the di-amino acid sequence tryptophan-aspartic acid in the N-terminal region and an additional glutamic acid residue in the C-terminal region of beta-endorphin - features found in fish beta-endorphin, but not tetrapod beta-endorphins. The western spadefoot toad POMC was 1,186 nucleotides in length, and exhibited an organizational scheme typical for tetrapod POMCs. However, the toad POMC did lack a paired basic amino acid proteolytic cleavage site N-terminal to the beta-MSH sequence. Thus, like rat POMC, it is doubtful that beta-MSH is an end product in either the toad brain or intermediate pituitary. At the amino acid level, the toad POMC had 76% sequence identity with Xenopus laevis POMC and 68% sequence identity with Rana ribidunda POMC. The use of these POMC sequences to assess phylogenetic relationships within anuran amphibians will be discussed. With respect to the fragment of S. multiplicatus proenkephalin cDNA, two metenkephalin sequences and the metenkephalin-RF sequence were found encoded in this fragment. As seen for X. laevis and R. ridibunda proenkephalin, a leuenkephalin sequence was not detected in the C-terminal region of the S. multiplicatus proenkephalin. The absence of a leuenkephalin sequence may be a common feature of anuran amphibian proenkephalins.
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PMID:Cloning of proopiomelanocortin from the brain of the african lungfish, Protopterus annectens, and the brain of the western spadefoot toad, Spea multiplicatus. 1042 92

Regulation of pituitary vasopressin V1b receptors plays a critical role in regulating pituitary adrenocorticotropic hormone (ACTH) secretion during adaptation to stress. The objective of this study was to isolate the promoter regulatory region of the V1b receptor gene to better understand the molecular mechanisms involved in V1b receptor regulation. Screening of a rat genomic library using probes directed to the coding region and to the 5'UTR of the rat V1b receptor resulted in the isolation of several clones containing the 5'upstream regions of the V1b receptor cDNA. Sequencing of an 11.2 Kb fragment revealed 8.2 Kb upsteam of the reported cDNA sequence, which contains a putative promoter regulatory region. The 3' end of the clone contained 1472 base pairs corresponding to the recognized cDNA sequence, followed by 1506 bp of unknown sequence located at the end of the sixth transmembrane domain, probably corresponding to an intron, characteristic of these family of receptors. An additional 161 bp intron was found in the 5'UTR, similar to that described in the rat oxytocin receptor gene. 5'RACE and RNase protection analysis mapped two major putative transcription start points at -830 and -861 bp from the starting methionine. Analysis of the putative promoter region showed no indication of a proximal TATA box, but the presence of a CACA box, a GAGA box, several AP-1 and AP-2 sites and a cluster of Sp1 sites upstream of the AP-2 sites. A luciferase construct containing a 2.1-kb of putative promoter, and part of the 5'UTR including the first intron, showed promoter activity when transfected into COS-7, CHO and PC12 cell lines but not in AtT-20 cells. A similar construct without the intron and distal 5'UTR sequence has no promoter activity in the same cell lines. In summary, the V1b receptor gene contains at least 3 exons and 2 introns. The 5'flanking sequence contains several potential sites for transcriptional regulation, and induced luciferace activity only in constructs containing intron 1, suggesting that the latter is important for receptor gene activation. The data provide bases for future analysis of the regulatory elements controlling V1b receptor transcription.
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PMID:Isolation and characterization of the promoter region of the rat vasopressin V1b receptor gene. 1079 83

In mammals, prodynorphin codes for three C-terminally extended forms of leu-enkephalin. This is not the case for the anuran amphibian, Bufo marinus. A combination of 3'RACE, RT-PCR and 5'RACE protocols was used to clone and characterize a prodynorphin cDNA from the brain of this amphibian that contained two met-enkephalin sequences. One met-enkephalin sequence was located at the N-terminal of Met(5)-dynorphin A(1-17), and the other met-enkephalin sequence was located in the N-terminal region of B. marinus prodynorphin in a position that aligned with a pentapeptide met-enkephalin site in mammalian proenkephalin. The latter B. marinus met-enkephalin sequence is flanked by sets of paired basic proteolytic cleavage sites. In addition to the extra met-enkephalin sequence and the Met(5)-dynorphin A(1-17) sequence, the B. marinus prodynorphin contained two C-terminally extended forms of leu-enkephalin [alpha-neo-endorphin and dynorphin B(1-13)]. In the toad precursor the alpha-neo-endorphin sequence is identical to human alpha-neo-endorphin. The B. marinus dynorphin B(1-13) sequence differs from human dynorphin B(1-13) by one amino acid (Thr(12) vs. Val(12)). Steady-state analysis suggests that dynorphin B(1-13) and possibly alpha-neo-endorphin may be cleaved to yield leu-enkephalin as an end-product in the amphibian brain. Finally, the alignment of the extra met-enkephalin sequence in the N-terminal of B. marinus prodynorphin with the corresponding met-enkephalin site in mammalian proenkephalin adds support to the hypothesis that the prodynorphin gene arose as a duplication of the proenkephalin gene.
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PMID:Identification of a fourth opioid core sequence in a prodynorphin cDNA cloned from the brain of the amphibian, Bufo marinus: deciphering the evolution of prodynorphin and proenkephalin. 1209 17

There is general agreement that the polypteriform fishes, like Polypterus senegalus, constitute a unique lineage in the evolution of the vertebrates. However, the precise position of these fishes had been a point of controversy since the time of Darwin and Huxley. There is now consensus that the polypteriform fishes are members of superorder Actinopterygii. However, within the Actinopterygii, it is still debatable as to whether the polypteriform fishes are an early offshoot of the Actinopterygii or a more recent sister group to the sturgeon and other extant chondrostean fishes. In this study the sequence of proopiomelanocortin (POMC), the common precursor for the melanocortins and beta-endorphin, was used to evaluate the phylogenetic position of the polypteriform fishes relative to other bony fishes. 3(')RACE and 5(')RACE protocols were used to amplify overlapping regions of a POMC cDNA from the brain of P. senegalus. The full-length POMC cDNA had an open reading frame that encoded 259 amino acids. As seen in most gnathostomes, P. senegalus POMC has three melanocortin sequences (ACTH/alpha-MSH, gamma-MSH, and beta-MSH), and a beta-endorphin region. For phylogenetic analysis, the following POMC sequences were aligned at the amino acid level and analyzed using a maximum parsimony algorithm: P. senegalus, dogfish, sturgeon A, paddlefish A, sockeye salmon A, tilapia, and gar. The dogfish POMC sequence was used as the out-group. In this analysis the P. senegalus POMC sequence formed a clade with the chondrostean POMC sequences (sturgeon A and paddlefish A), and not with the neopterygian sequences (sockeye salmon A, tilapia, and gar). P. senegalus POMC is remarkably similar to sturgeon POMC A. In particular, in both precursors there is evidence for degeneration at the proteolytic cleavage site that precedes the gamma-MSH sequence. Based on the analysis of this nuclear gene it would appear that P. senegalus belongs to a branch of the chrondrostean lineage rather than representing a lineage of ray-finned fish that is ancestral to the chondrostean and neoptyergian ray-finned fishes. Alternatively, if the polypteriform fishes are in fact an early offshoot of the Actinopterygii (the traditional view), then the observations made for P. senegalus POMC relative to the chondrostean POMC sequences is the result of convergence.
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PMID:Characterizing a proopiomelanocortin cDNA cloned from the brain of the Bichir, Polypterus senegalus: evaluating phylogenetic relationships among ray-finned fish. 1463 41

Proopiomelanocortin (POMC) is a precursor protein that contains the sequences of several bioactive peptides including adrenocorticotropin (ACTH), beta-endorphin (beta-EP), and melanocyte-stimulating-hormone (MSH). POMC is synthesized in the pituitary gland, brain, and many peripheral tissues. Immunoreactive POMC-derived peptides as well as POMC-like mRNA have been evidenced in several nonpituitary tissues, thus suggesting that POMC is actively synthesized by these tissues. The present study was aimed at evaluating if also in the case of stallion POMC-derived peptide, beta-EP, is produced locally in the testis, thus playing effects in a paracrine/autocrine fashion. To investigate this hypothesis the POMC gene expression was analyzed using 3' RACE-PCR and Northern Blot approaches in the testis and epididimys of stallion; moreover, immunocytochemical localization for beta-EP was also performed through confocal laser microscopy. The immunofluorescence results showed a positive beta-EP reaction not only in cellular nest of pituitary but also in the testis and genital tract of stallion, which function could be related with sperm mobility. Such role seem not to be no dependent on the peptide synthesized locally, because the molecular biology approach demonstrated the presence of POMC transcript in the pituitary only. In fact the Northern Blot analysis showed the presence of a single POMC transcript in the pituitary while no signal was detected in the testis and epididimys. The same results were obtained by applied 3' RACE-PCR analysis. In conclusion, opioid-derived peptide beta-EP is present in the genital tract of stallion, but is not locally produced as in other mammalian, and nonmammalian models; its possible biological function at testicular level could be linked to a long-loop feed-back mechanisms.
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PMID:Proopiomelanocortin gene expression and beta-endorphin localization in the pituitary, testis, and epididymis of stallion. 1617 84

Feather coloration in chickens mainly depends on melanin produced by melanocytes located in the feather follicles. The melanocortin 1 receptor (MC1R) on follicular melanocytes regulates melanin synthesis; however, the source of the melanocortins that interact with the receptors remains unclear. In this study, we examine the potential expression of melanocortins and characterize the mRNAs for the precursor pro-opiomelanocortin (POMC) in chicken feather follicles. Reverse transcription-polymerase chain reaction (RT-PCR) revealed the expression of mRNAs for POMC, prohormone convertase 1 (PC1) and PC2, and western blotting detected adrenocorticotropic hormone (ACTH)-related products of POMC processing in feather follicles, suggesting that melanocortins are produced locally in the tissues of chickens. A combination of 5'RACE (rapid amplification of cDNA 5' end), 3'RACE and RT-PCR analyzes identified two classes of POMC mRNA, class a and class b, which encode the same full-length POMC protein but have different non-coding leader exons. Class a mRNAs were expressed specifically in feather follicles, whereas class b mRNAs were expressed in the pituitary, hypothalamus, and various peripheral tissues that we examined. Within the feather follicles, the class a mRNAs were distributed in epidermal layers from middle to distal locations, whereas the class b mRNAs were mainly expressed in pulp at proximal locations. Our findings suggest that feather pigmentation is regulated by locally produced melanocortins, and indicate that the melanocortins encoded by the different classes of POMC mRNAs may play different intra-follicular roles in chickens. This is the first report that demonstrates alternative promoter usage generating different full-length POMC mRNAs in vertebrates.
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PMID:Feather follicles express two classes of pro-opiomelanocortin (POMC) mRNA using alternative promoters in chickens. 2118