Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P06889 (Mol)
630,302 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The capacity for the neurotrophic factor PACAP38 to regulate expression of nerve growth factor (NGF)-trkA receptors in PC12 cells has been examined. Treatment of PC12 cells with 5 nM PACAP38 for 48 h elicited a 2.5-fold increase in 125I-NGF binding sites. FACS and Western analysis of trkA receptor protein indicate an abundance of receptors. The PACAP38-selective antagonist PACAP 6-38 blocked trkA receptor upregulation elicited by PACAP38. The expression of epidermal growth factor receptors was not affected by PACAP38 suggesting that upregulation of trkA represents a selective effect of this neurotrophic peptide. Similarly, expression of the pan-neurotrophin binding receptor p75 was not altered by PACAP38 treatment. In addition to effects on trkA observed in wild-type PC12 cells, PACAP38 stimulated an increase in the level of expressed human trkA receptors stably transfected into PC12 cells. PACAP38 provoked an increase in basal and NGF-stimulated phosphorylation of trkA. Enhanced phosphorylation of trkA was detected as early as 6 h following addition of PACAP38 and was maximal at 48 h. Increased incorporation of phosphate occurs on both serine and tyrosine residues of trkA. These results suggest that PACAP38 is able to promote upregulation of trkA receptors, an event associated with elevated serine/tyrosine phosphorylation of trkA.
Mol Cell Biol Res Commun 1999 Aug
PMID:Heterologous upregulation of nerve growth factor-TrkA receptors in PC12 cells by pituitary adenylate cyclase-activating polypeptide (PACAP). 1054 32

Pituitary adenylate cyclase-activating polypeptide (PACAP) is a pleiotropic neuropeptide and its specific receptor (the PAC(1) receptor) is widely distributed in the rat brain. It has been reported that alternative splicing of the region encoding the third intracellular loop of the PAC(1) receptor generates six isoforms which are differentially coupled to signal transduction pathways, but the precise distribution and localization of these splice isoforms in the brain remain to be determined. Using the initial specific primer pairs which correspond to the 'hip' or 'hop' types of receptors for the solution-phase reverse transcription-polymerase chain reaction (RT-PCR), we demonstrated that the major splice variants of the PAC(1) receptor in various regions of the rat brain are the short splice isoform 'PAC(1)-R-s' which does not contain either the 'hip' or 'hop' cassette and the another splice isoform, 'PAC(1)-R-hop', which contains the 'hop' cassette. With an innovative molecular histochemical technique, in situ RT-PCR, we determined that these two splice isoforms are both intensely expressed in the mitral cells of the olfactory bulb, the Purkinje cells of the cerebellum, the pyramidal cells of the hippocampus and neocortex, and many neurons in the nuclei of hypothalamus and thalamus as well as other regions. The initial mapping of the cell type-specific expression of these two splice variants of the PAC(1) receptor provides the basis for a better understanding of the functional significance of the PAC(1)-R and its ligand PACAP in various brain regions.
Brain Res Mol Brain Res 2000 Jan 10
PMID:Cellular distribution of the splice variants of the receptor for pituitary adenylate cyclase-activating polypeptide (PAC(1)-R) in the rat brain by in situ RT-PCR. 1064 99

We describe a screen for new imprinted human genes, and the identification in this way of ZAC (zinc finger protein which regulates apoptosis and cell cycle arrest)/ PLAGL1 (pleomorphicadenoma of the salivary gland gene like 1) as a strong candidate gene for transient neonatal diabetes mellitus (TNDM). To screen for imprinted genes, we compared parthenogenetic DNA from the chimeric patient FD and androgenetic DNA from hydatidiform mole, using restriction landmark genome scanning for methylation. This resulted in identification of two novel imprinted loci, one of which (NV149) we mapped to the TNDM region of 6q24. From analysis of the corresponding genomic region, it was determined that NV149 lies approximately 60 kb upstream of the ZAC / PLAGL1 gene. RT-PCR analysis was used to confirm that this ZAC / PLAGL1 is expressed only from the paternal allele in a variety of tissues. TNDM is known to result from upregulation of a paternally expressed gene on chromosome 6q24. The paternal expression, map position and known biological properties of ZAC / PLAGL1 make it highly likely that it is the TNDM gene. In particular, ZAC / PLAGL1 is a transcriptional regulator of the type 1 receptor for pituitary adenylate cyclase-activating polypeptide, which is the most potent known insulin secretagog and an important mediator of autocrine control of insulin secretion in the pancreatic islet.
Hum Mol Genet 2000 Feb 12
PMID:The cell cycle control gene ZAC/PLAGL1 is imprinted--a strong candidate gene for transient neonatal diabetes. 1065 56

The present study was designed to determine whether progesterone might have a role in gonadotrophin-induced pituitary adenylate cyclase-activating polypeptide (Pacap) gene expression in rat ovary. Northern blot analysis revealed that treatment of pregnant mare's serum gonadotrophin (PMSG)-primed immature rats with the progestin antagonist RU486 or an inhibitor of 3beta-hydroxysteroid dehydrogenase epostane, 1 h before HCG, resulted in a dose-dependent inhibition of the HCG-induced Pacap gene expression. In-situ hybridization demonstrated that the number of pre-ovulatory follicles expressing Pacap mRNA in their granulosa cells was greatly reduced in ovaries treated with RU486. Moreover, the suppressive effect of RU486 or epostane on the LH-induced Pacap gene expression in cultured pre-ovulatory follicles was reversed by co-treatment with the synthetic progestin R5020. We further cloned the 5'-flanking region of the rat Pacap gene and identified the presence of a consensus progesterone receptor element. When luciferase fusion genes containing Pacap gene promoter were transiently transfected into granulosa cells of pre-ovulatory follicles, luciferase activity was markedly stimulated by LH. Treatment with RU486 or epostane resulted in partial suppression of LH-stimulated PACAP promoter activity. Taken together, these results indicate that progesterone, acting through progesterone receptors, plays a role in gonadotrophin induction of Pacap gene expression in granulosa cells of pre-ovulatory follicles, and thereby may be involved in the process of ovulation.
Mol Hum Reprod 2000 Mar
PMID:Involvement of progesterone in gonadotrophin-induced pituitary adenylate cyclase-activating polypeptide gene expression in pre-ovulatory follicles of rat ovary. 1069 71

Pituitary adenylate cyclase activating polypeptide (PACAP) was isolated from ovine hypothalamus and known to stimulate the production of cAMP in anterior pituitary cells. In the recent report, the expression of PACAP was detected in preovulatory follicles, and treatment with PACAP stimulated the production of progesterone and prostaglandin E(2) through the action of AC and PLC pathways in the ovary. PACAP binds to three type receptors. Type I A receptor is coupled to adenylate cyclase (AC) and phospholipase C (PLC) pathways, while type I B and type II receptors are only coupled to AC. Thus, the present study aimed to evaluate the temporal expression of PACAP and its type I A receptor mRNAs in the rat ovary after treatment with pregnant mare's serum gonadotropin and human chorionic gonadotropin (hCG). Northern blot analysis showed that PACAP transcripts were transiently expressed from 3-9 hr after hCG treatment, reaching a maximum at 6 hr. During these time points, PACAP mRNAs were specifically and strongly expressed in granulosa cells and cumulus cells of large preovulatory follicles and interstitial glandular cells. Type I A receptor mRNAs were also transiently expressed in granulosa cells of large preovulatory follicles from 3-9 hr after hCG treatment. PACAP and its type I A receptor mRNAs were expressed in the same preovulatory follicles. These results demonstrate that PACAP acts as an autoregulator or pararegulator through type I A receptor in granulosa cells and cumulus cells of large preovulatory follicles. Thus, we suggest that PACAP may have a critical role in granulosa cells of preovulatory follicles for the preparation of ovulation.
Mol Reprod Dev 2000 Apr
PMID:Expression of pituitary adenylate cyclase activating polypeptide (PACAP) and PACAP type I A receptor mRNAs in granulosa cells of preovulatory follicles of the rat ovary. 1069 44

Pituitary adenylate cyclase-activating polypeptide (PACAP) regulates pituitary hormone biosynthesis and secretion through its cognate receptors. PACAP also plays an important role in the regulation of ovarian steroid biosynthesis. If so, there might be a feedback regulation of hypothalamic PACAP synthesis by the pituitary and by ovarian steroids. In the present study, we used RNase protection assays to determine changes in mRNA levels of PACAP and type I PACAP receptor (PAC(1)) under the conditions of ovariectomy and replacement with ovarian steroids. Progesterone (P) alone or in combination with estradiol (E) induced significant increases in PACAP mRNA level in the medial basal hypothalamus (MBH) and PAC(1) mRNA levels in MBH and the preoptic area (POA). This finding suggests that feedback regulation takes place between the ovary and hypothalamic PACAP neurons. P is known to be a major regulatory feedback factor for hypothalamic luteinizing hormone-releasing hormone (LHRH) neurons, but P receptor is not present in these neurons. Therefore, we examined a possible involvement of PACAP in the feedback regulatory pathway of P to LHRH neurons. After an antisense PAC(1) oligodeoxynucleotide (ODN) was i.c.v.-injected into the third ventricle of E and P-treated rats, LHRH mRNA levels were determined. The ODN markedly decreased the P-induced increase in the LHRH mRNA level. Taken together, the present data suggest that PACAP may play a role as a mediator in the regulation of LHRH synthetic machinery by stimulatory feedback of P.
Brain Res Mol Brain Res 2000 May 31
PMID:Progesterone increases mRNA levels of pituitary adenylate cyclase-activating polypeptide (PACAP) and type I PACAP receptor (PAC(1)) in the rat hypothalamus. 1089 85

The purpose of this research was to isolate and characterize the gene encoding growth hormone-releasing hormone (GRF) and pituitary adenylate cyclase-activating polypeptide (PACAP) from the zebrafish. The gene is comprised of five exons with two distinct peptides encoded on separate exons, GRF on exon 4 and PACAP on exon 5. Our evidence indicates that the zebrafish genome contains a single copy of the GRF-PACAP gene. The tissue distribution pattern of the mRNA transcript shows expression in the brain, eye, gastrointestinal tract, ovary and testis; each transcript was sequenced and found to be identical to the gene. This is the first report of GRF-PACAP mRNA expression in the eye of a non-mammalian species. Evidence that a duplication of the PACAP gene gave rise to the vasoactive intestinal peptide (VIP) gene is supported by the high amino acid sequence identity between PACAP in zebrafish and VIP in other fish species.
Mol Cell Endocrinol 2000 Jul 25
PMID:Characterization of the gene encoding both growth hormone-releasing hormone (GRF) and pituitary adenylate cyclase-activating polypeptide (PACAP) in the zebrafish. 1094 Apr 99

To elucidate the functional role of the second extracellular loop of human vasoactive intestinal polypeptide/pituitary adenylate cyclase-activating polypeptide (VIP/PACAP) receptor (hVPAC1R), surface expression, ligand binding, and receptor activation were analyzed. Amino acids in the entire second extracellular loop were individually substituted by alanine by site-directed mutagenesis. The mutant and wild-type receptors were transiently expressed in HEK293 cells and purified cell membranes were tested for the ability to bind VIP, while the receptor activity was measured as potency of cAMP production analysed on intact cells. Surface expression of the substituted conserved residues, W286A, I289A, W294A, and W295A, was evidently decreased to 20-30% compared to the wild-type expression. W286A also showed an significantly reduced potency of cAMP production. Substituted residues as F280A, E281A, and G284A showed a significant reduction in the potency of stimulated cAMP production amounting to 8-46-fold, compared to the wild-type with unaffected surface expression and VIP binding. These results indicate that some residues in the second extracellular loop of the human VPAC1R participate in the active mechanism of a ligand-mediated response without being directly involved in the binding of VIP.
J Mol Neurosci 2000 Jun
PMID:Role of second extracellular loop in the function of human vasoactive intestinal polypeptide/pituitary adenylate cyclase activating polypeptide receptor 1 (hVPAC1R). 1098 89

Growth hormone-releasing hormone (GHRH) and pituitary adenylate cyclase-activating polypeptide (PACAP) belong to the same superfamily of regulatory neuropeptides and have both been characterized on the basis of their hypophysiotropic activities. This review describes the molecular evolution of the GHRH/PACAP gene family from urochordates to mammals and presents the hypothesis that the respective roles of GHRH and PACAP in the control of GH secretion are totally inverted in phylogenetically distant groups of vertebrates. In mammals, GHRH and PACAP originate from distinct precursors whereas, in all submammalian taxa investigated so far, including birds, amphibians and fish, a single precursor encompasses a GHRH-like peptide and PACAP. In mammals, GHRH-containing neurons are confined to the infundibular and dorsomedial nuclei of the hypothalamus while PACAP-producing neurons are widely distributed in hypothalamic and extrahypothalamic areas. In fish, both GHRH- and PACAP-immunoreactive neurons are restricted to the diencephalon and directly innervate the adenohypophysis. In mammals and birds, GHRH plays a predominant role in the control of GH secretion. In amphibians, both GHRH and PACAP are potent stimulators of GH release. In fish, PACAP strongly activates GH release whereas GHRH has little or no effect on GH secretion. The GHRH/PACAP family of peptides thus provides a unique model in which to investigate the structural and functional facets of evolution.
J Mol Endocrinol 2000 Oct
PMID:Molecular evolution of the growth hormone-releasing hormone/pituitary adenylate cyclase-activating polypeptide gene family. Functional implication in the regulation of growth hormone secretion. 1101 44

Central administration of an antisense oligodeoxynucleotide against type I pituitary adenylate cyclase-activating polypeptide receptor suppresses synthetic activities of LHRH-LH axis during the pubertal process In the present study, we determined the expression of pituitary adenylate cyclase-activating polypeptide (PACAP) and PACAP receptor type I (PAC1) genes during juvenile development and the pubertal process. Female rats were assigned--based on uterine weights, the presence and abundance of uterine fluid, and their vaginal patency--to one of the following: anestrus (AE), early proestrus (EP), late proestrus (LP) or first estrus (E). The hypothalami from 22-, 24- and 26-day-old animals and from those in the peripubertal phases of AE, EP, LP and E were collected, and the content of PACAP and PAC1 mRNA was assessed. These levels were found to decrease in EP and LP. To determine the effect of PACAP on prepubertal luteinizing hormone-releasing hormone (LHRH) and LH synthesis through PAC1, a PAC1 antisense oligodeoxynucleotide (ODN) was i.c.v.-administered, and mRNA levels of LHRH, LH beta, and LHRH receptor (LHRH-R) were determined. Prepubertal increases in LHRH, LH beta, and LHRH-R mRNA levels were markedly suppressed, and the onset of puberty was delayed by the i.c.v. injection of the antisense PAC1 ODN. These data suggest that PACAP may play a role in the regulation of hypothalamic LHRH neurons, through which it regulates synthetic machinery of pituitary LH, during the pubertal process.
Brain Res Mol Brain Res 2000 Aug 14
PMID:Central administration of an antisense oligodeoxynucleotide against type I pituitary adenylate cyclase-activating polypeptide receptor suppresses synthetic activities of LHRH-LH axis during the pubertal process. 1103 27


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