Neuropeptide pituitary adenylate cyclase-activating polypeptide (PACAP) is a pleiotropic hormone that is involved in numerous physiologic functions. The present study examines the presence and the functional significance of PACAP and its receptor in the brain and astrocytes of tilapia (Oreochromis mossambicus). This is the first demonstration of the full-length nucleotide sequence of tPACAP gene in tilapia pituitary, brain, and cultured astrocytes. Two cDNA variants of the growth hormone–releasing hormone (GHRH)–PACAP gene were identified in tilapia pituitary, brain, and cultured astrocytes as a result of exon skipping with a long form (271 bp) encoding both tPACAP38 and tGHRH and a short form (166 bp) encoding only tPACAP38. The short form was found to be more abundant in astrocytes. Addition of ovine PACAP38 (1 nM) to cultured astrocytes significantly stimulated the expression of tPACAP38 at 4 hrs, but the effect dropped after 8 hrs of treatment. By contrast, the expression of PACAP type I receptor (PAC1-R) mRNA in the astrocytes was not responsive to PACAP38 treatment. The tPACAP38 expression also was activated by the cAMP analog, dibutyryl-cAMP, in a dose-dependent manner. Adding high salinity (170 mM NaCl, 500 mOsm/kg osmolarity) to cultured medium substantially increased astroglial tPACAP38 expression over 4 hrs to a level that was maintained for 16 hrs. This observation was not found when mannitol (270 mM) was supplemented as an osmolarity-enhancing agent (500 mOsm/ kg). Taken together, tPACAP expression in tilapia astrocytes was well regulated by exogenous PACAP, cAMP, and salinity and might be involved in the adaptation to high salinity when the fish is in a seawater environment.
Get full access to this article
View all access options for this article.
References
1.
Miyata A, Arimura A, Dahl RR, Minamino N, Uehara A, Jiang L, Culler, MD, Coy DH. Isolation of a novel 38 residue-hypothalamic polypeptide which stimulates adenylate cyclase in pituitary cells. Biochem Biophys Res Commun164:567–574, 1989.
2.
Miyata A, Jiang L, Dahl RD, Kitada C, Kubo K, Fujino M, Minamino N, Arimura A. Isolation of a neuropeptide corresponding to the N-terminal 27 residues of the pituitary adenylate cyclase activating polypeptide with 38 residues (PACAP38). Biochem Biophys Res Commun170:643–648, 1990.
3.
McRory JE, Sherwood NM. Two protochordate genes encode pituitary adenylate cyclase-activating polypeptide and related family members. Endocrinology138:2380–2390, 1997.
4.
McRory JE, Parker DB, Ngamvongchon S, Sherwood NM. Sequence and expression of cDNA for pituitary adenylate cyclase activating polypeptide (PACAP) and growth hormone-releasing hormone (GHRH)-like peptide in catfish. Mol Cell Endocrinol108:169–177, 1995.
5.
Fradinger EA, Sherwood NM. Characterization of the gene encoding both growth hormone-releasing hormone (GRF) and pituitary adenylate cyclase-activating polypeptide (PACAP) in the zebrafish. Mol Cell Endocrinol165: 211–219, 2000.
6.
Parker DB, Coe IR, Dixon GH, Sherwood NM. Two salmon neuropeptides encoded by one brain cDNA are structurally related to members of the glucagon superfamily. Eur J Biochem215:439–448, 1993.
7.
Small BC, Nonneman D. Sequence and expression of a cDNA encoding both pituitary adenylate cyclase activating polypeptide and growth hormone-releasing hormone-like peptide in channel catfish (Ictalurus punctatus). Gen Comp Endocrinol122:354–363, 2001.
8.
Wong AO, Li WS, Lee EK, Leung MY, Tse LY, Chow BK. Pituitary adenylate cyclase activating polypeptide as a novel hypophysiotropic factor in fish. Biochem Cell Biol78:229–243, 2000.
9.
Hu Z, LelievreV, Tam J, Cheng JW, Fuenzalida G, Zhou X. Molecular cloning of growth hormone-releasing hormone/pituitary adenylate cyclase-activating polypeptide in the frog Xenopus laevis: brain distribution and regulation after castration. Endocrinology141:3366–3376, 2000.
10.
Alexandre D, Vaudry H, Jegou S, Anouar Y. Structure and distribution of the mRNAs encoding pituitary adenylate cyclase-activating poly-peptide and growth hormone-releasing hormone-like peptide in the frog, Rana ridibunda. J Comp Neurol421:234–246, 2000.
11.
McRory JE, Parker DB, Sherwood NM. Expression and alternative processing of a chicken gene encoding both growth hormone-releasing hormone and pituitary adenylate cyclase-activating polypeptide. DNA Cell Biol16:95–102, 1997.
12.
Yoo SJ, You S, Kim H, Kim SC, Choi YJ, El Halawani M. Molecular cloning and characterization of alternatively spliced transcripts of the turkey pituitary adenylate cyclase-activating polypeptide. Gen Comp Endocrinol120:326–335, 2000.
13.
Matsuda K, Nagano Y, Uchiyama M, Onoue S, Takahashi A, Kawauchi H, Shioda S. Pituitary adenylate cyclase-activating poly-peptide (PACAP)-like immunoreactivity in the brain of a teleost, Uranoscopus japonicus: immunohistochemical relationship between PACAP and adenohypophysial hormones. Regul Pept126:129–136, 2005.
14.
Vaudry D, Gonzalez BJ, Basille M, Yon L, Fournier A, Vaudry H. Pituitary adenylate cyclase-activating polypeptide and its receptors: from structure to functions. Pharmacol Rev52:269–324, 2000.
15.
Sherwood NM, Krueckl SL, McRory JE. The origin and function of the pituitary adenylate cyclase-activating polypeptide (PACAP)/glucagons superfamily. Endocr Rev21:619–670, 2000.
16.
Harmar AJ, Arimura A, Gozes I, Journot L, Laburthe M, Pisegna JR, Rawlings SR, Robberecht P, Said SI, Sreedharan SP, Wank SA, Waschek JA. International Union of Pharmacology. XVIII. Nomenclature of receptors for vasoactive intestinal peptide and pituitary adenylate cyclase-activating polypeptide. Pharmacol Rev50:265–270, 1998.
17.
Hashimoto H, Ishihara T, Shigemoto R, Mori K, Nagata S. Molecular cloning and tissue distribution of a receptor for pituitary adenylate cyclase-activating polypeptide. Neuron11:333–342, 1993.
18.
Ishihara T, Shigemoto R, Mori K, Takahashi K, Nagata S. Functional expression and tissue distribution of a novel receptor for vasoactive intestinal polypeptide. Neuron8:811–819, 1992.
19.
Lutz EM, Sheward WJ, West KM, Morrow JA, Fink G, Harmar AJ. The VIP2 receptor: molecular characterization of a cDNA encoding a novel receptor for vasoactive intestinal peptide. FEBS Lett334:3–8, 1993.
20.
Delporte C, Poloczek P, de Neef P, Vertongen P, Ciccarelli E, Svoboda M, Herchuelz A, Winand J, Robberecht P. Pituitary adenylate cyclase-activating polypeptide (PACAP) and vasoactive intestinal peptide stimulate two signaling pathways in CHO cells stably transfected with the selective type I PACAP receptor. Mol Cell Endocrinol107:71–76, 1995.
21.
Pisegna JR, Wank SA. Cloning and characterization of the signal transduction of four splice variants of the human pituitary adenylate cyclase- activating polypeptide receptor. Evidence for dual coupling to adenylate cyclase and phospholipase C. J Biol Chem271:17267–17274, 1996.
22.
Schomerus E, Poch A, Bunting R, Mason WT, McArdle CA. Effects of pituitary adenylate cyclase-activating polypeptide in the pituitary: activation of two signal transduction pathways in the gonadotrope-derived alpha T3–1 cell line. Endocrinology134:315–323, 1994.
23.
Tatsuno I, Morio H, Tanaka T, Uchida D, Hirai A, Tamura Y, Saito Y. Pituitary adenylate cyclase-activating polypeptide (PACAP) is a regulator of astrocytes: PACAP stimulates proliferation and production of interleukin 6 IL-6, but not nerve growth factor (NGF), in cultured rat astrocyte. Ann N Y Acad Sci805:482–488, 1996.
24.
Tatsuno I, Gottschall PE, Koves K, Arimura A. Demonstration of specific binding sites for pituitary adenylate cyclase activating polypeptide (PACAP) in rat astrocytes. Biochem Biophys Res Commun168:1027–1033, 1990.
25.
Tatsuno I, Gottschall PE, Arimura A. Specific binding sites for pituitary adenylate cyclase-activating polypeptide (PACAP) in rat cultured astrocytes: molecular identification and interaction with vasoactive intestinal peptide (VIP). Peptides12:617–621, 1991.
26.
Tatsuno I, Arimura A. Pituitary adenylate cyclase-activating polypep-tide (PACAP) stimulates intracellular free calcium concentration on rat cultured astrocytes in type-2, but not in type-1. Brain Res662:1–10, 1994.
27.
Moroo I, Tatsuno I, Uchida D, Tanaka T, Saito J, Saito Y, Hirai A. Pituitary adenylate cyclase-activating polypeptide (PACAP) stimulates mitogen-activated protein kinase (MAPK) in cultured rat astrocytes. Brain Res795:191–196, 1998.
28.
Wong AO, Leung MY, Shea WL, Tse LY, Chang JP, Chow BK. Hypophysiotropic action of pituitary adenylate cyclase-activating polypeptide (PACAP) in the goldfish: immunohistochemical demonstration of PACAP in the pituitary, PACAP stimulation of growth hormone release from pituitary cells, and molecular cloning of pituitary type I PACAP receptor. Endocrinology139:3465–3479, 1998.
29.
Parker DB, Power ME, Swanson P, Rivier J, Sherwood NM. Exon skipping in the gene encoding pituitary adenylate cyclase-activating polypeptide in salmon alters the expression of two hormones that stimulate growth hormone release. Endocrinology138:414–423, 1997.
30.
Montero M, Yon L, Rousseau K, Arimura A, Fournier A, Dufour S. Localization of pituitary adenylate cyclase-activating polypeptide in the central nervous system of the European eel Anguilla anguilla: stimulatory effect of PACAP on GH secretion. Ann N Y Acad Sci865:475–477, 1998.
31.
Rousseau K, Le Belle N, Pichavant K, Marchelidon J, Chow BK, Boeuf G. Pituitary growth hormone secretion in the turbot, a phylogenetically recent teleost, is regulated by a species-specific pattern of neuropeptides. Neuroendocrinology74:375–385, 2001.
32.
Wirachowsky NR, Kwong P, Yunker WK, Johnson JD, Chang JD. Mechanisms of action of pituitary adenylate cyclase-activating polypeptide (PACAP) on growth hormone release from dispersed goldfish pituitary cells. Fish Physiol Biochem23:201–214, 2000.
33.
Chang JP, Wirachowsky NR, Kwong P, Johnson JD. PACAP stimulation of gonadotropin-II secretion in goldfish pituitary cells: mechanisms of action and interaction with gonadotropin releasing hormone signaling. J Neuroendocrinol13:540–550, 2001.
34.
Matsuda K, Kashimoto K, Higuchi T, Yoshida T, Uchiyama M, Shioda S. Presence of pituitary adenylate cyclase-activating polypeptide (PACAP) and its relaxant activity in the rectum of a teleost, the stargazer, Uranoscopus japonicus. Peptides21:821–827, 2000.
35.
Olsson C, Holmgren S. PACAP and nitric oxide inhibit contractions in the proximal intestine of the Atlantic cod, Gadus morhua. J Exp Biol203:575–583, 2000.
36.
Montpetit CJ, Perry SF. Vasoactive intestinal polypeptide- and pituitary adenylate cyclase-activating polypeptide-mediated control of catechol-amine release from chromaffin tissue in the rainbow trout, Oncorhyn-chus mykiss. J Endocrinol166:705–714, 2000.
37.
Mathieu M, Ciarlo M, Trucco N, Griffero F, Damonte G, Salis A, Vallarino M. Pituitary adenylate cyclase-activating polypeptide in the brain, spinal cord and sensory organs of the zebrafish, Danio rerio, during development. Brain Res Dev Brain Res151:169–185, 2004.
38.
Wang Y, Wong AO, Ge W. Cloning, regulation of messenger ribonucleic acid expression, and function of a new isoform of pituitary adenylate cyclase-activating polypeptide in the zebrafish ovary. Endocrinology144:4799–4810, 2003.
39.
Gong HY, Wu JL, Huang WT, Lin CJ, Weng CF. Response to acute changes in salinity of two different muscle type creatine kinase isoforms, from euryhaline teleost (Oreochromis mossambicus) gills. Biochim Biophys Acta1675:184–191, 2004.
40.
Weng CF, Chiang CC, Gong HY, Chen MH, Lin CJ, Huang WT, Cheng CY, Hwang PP, Wu JL. Acute changes in gill Na+-K+-ATPase and creatine kinase in response to salinity changes in the euryhaline teleost, tilapia (Oreochromis mossambicus). Physiol Biochem Zool75: 29–36, 2002.
41.
Lin LY, Chiang CC, Gong HY, Cheng CY, Hwang PP, Weng CF. Cellular distributions of creatine kinase in branchia of euryhaline tilapia (Oreochromis mossambicus). Am J Physiol Cell Physiol284:C233–C241, 2003.
42.
Weng CF, Chiang CC, Gong HY, Chen MH, Huang WT, Cheng CY, Wu JL. Bioenergetics of adaptation to a salinity transition in euryhaline teleost (Oreochromis mossambicus) brain. Exp Biol Med (Maywood)227:45–50, 2002.
43.
Arima H, Yamamoto N, Sobue K, Umenishi F, Tada T, Katsuya H, Asai K. Hyperosmolar mannitol simulates expression of aquaporins 4 and 9 through a p38 mitogen-activated protein kinase-dependent pathway in rat astrocytes. J Biol Chem278:44525–44534, 2003.
44.
Bitoun M, Tappaz M. Gene expression of the transporters and biosynthetic enzymes of the osmolytes in astrocyte primary cultures exposed to hyperosmotic conditions. Glia32:165–176, 2000.
45.
Xu D, Wang L, Olson JE, Lu L. Asymmetrical response of p38 kinase activation to volume changes in primary rat astrocytes. Exp Biol Med (Maywood)226:927–933, 2001.
46.
Parkerson KA, Sontheimer H. Contribution of chloride channels to volume regulation of cortical astrocytes. Am J Physiol Cell Physiol284:C1460–C1467, 2003.
47.
Fischer R, Schliess F, Haussinger D. Characterization of the hypo-osmolarity-induced Ca2+ response in cultured rat astrocytes. Glia20: 51–58, 1997.
48.
Franke B, Figiel M, Engele J. CNS glia are targets for GDNF and neurturin. Histochem Cell Biol110:595–601, 1998.
49.
Dejda A, Sokolowska P, Nowak JZ. Neuroprotective potential of three neuropeptides PACAP, VIP and PHI. Pharmacol Rep57:307–320, 2005.
50.
Tatsuno I, Morio H, Tanaka T, Uchida D, Hirai A, Tamura Y, Saito Y. Pituitary adenylate cyclase-activating polypeptide (PACAP) is a regulator of astrocytes: PACAP stimulates proliferation and production of interleukin 6 IL-6, but not nerve growth factor (NGF), in cultured rat astrocyte. Ann N Y Acad Sci805:482–488, 1996.
51.
Matsuda K, Nagano Y, Uchiyama M, Takahashi A, Kawauchi H. Immunohistochemical observation of pituitary adenylate cyclase-activating polypeptide (PACAP) and adenohypophysial hormones in the pituitary of a teleost, Uranoscopus japonicus. Zoolog Sci22:71–76, 2005.
52.
Montero M, Yon L, Rousseau K, Arimura A, Fournier A, Dufour S. Distribution, characterization, and growth hormone-releasing activity of pituitary adenylate cyclase-activating polypeptide in the European eel, Anguilla anguilla. Endocrinology139:4300–4310, 1998.
53.
Montpetit CJ, Shahsavarani A, Perry SF. Localization of VIP-binding sites exhibiting properties of VPAC receptors in chromaffin cells of rainbow trout (Oncorhynchus mykiss). J Exp Biol206:1917–1927, 2003.
54.
Fradinger EA, Tello JA, Rivier JE, Sherwood NM. Characterization of four receptor cDNAs: PAC1, VPAC1, a novel PAC1 and a partial GHRH in zebrafish. Mol Cell Endocrinol.231:49–63, 2005.
55.
Matsuda K, Maruyama K, Miura T, Uchiyama M, Shioda S. Anorexigenic action of pituitary adenylate cyclase-activating polypeptide (PACAP) in the goldfish: feeding-induced changes in the expression of mRNAs for PACAP and its receptors in the brain, and locomotor response to central injection. Neurosci Lett386:9–13, 2005.
56.
Armstrong BD, Hu Z, Abad C, Yamamoto M, Rodriguez WI, Cheng J, Tam J, Gomariz RP, Patterson PH, Waschek JA. Lymphocyte regulation of neuropeptide gene expression after neuronal injury. J Neurosci Res74:240–247, 2003.
57.
Adams BA, Lescheid DW, Vickers ED, Crim LW, Sherwood NM. Pituitary adenylate cyclase-activating polypeptide and growth hormone-releasing hormone-like peptide in sturgeon, whitefish, grayling, flounder and halibut: cDNA sequence, exon skipping and evolution. Regul Pept109:27–37, 2002.
58.
Krueckl SL, Sherwood NM. Developmental expression, alternative splicing and gene copy number for the pituitary adenylate cyclase-activating polypeptide (PACAP) and growth hormone-releasing hormone (GRF) gene in rainbow trout. Mol Cell Endocrinol182:99–108, 2001.
59.
Irwin DM, Wong J. Trout and chicken proglucagon: alternative splicing generates mRNA transcripts encoding glucagon-like peptide 2. Mol Endocrinol9:267–277, 1995.
60.
Talbot RT, Dunn IC, Wilson PW, Sang HM, Sharp PJ. Evidence for alternative splicing of the chicken vasoactive intestinal polypeptide gene transcript. J Mol Endocrinol15:81–91, 1995.
61.
Linder S, Barkhem T, Norberg A, Persson H, Schalling M, Hokfelt T. Structure and expression of the gene encoding the vasoactive intestinal polypeptide precursor. Proc Natl Acad Sci U S A84:605–609, 1987.
62.
Ko C, Park-Sarge OK. Progesterone receptor activation mediates LH-induced type-I pituitary adenylate cyclase-activating polypeptide receptor (PAC1) gene expression in rat granulosa cells. Biochem Biophys Res Commun277:270–279, 2000.
63.
Suzuki R, Arata S, Nakajo S, Ikenaka K, Kikuyama S, Shioda S. Expression of the receptor for pituitary adenylate cyclase-activating polypeptide (PAC1-R) in reactive astrocytes. Brain Res Mol Brain Res115:10–20, 2003.
64.
Yamamoto K, Hashimoto H, Hagihara N, Nishino A, Fujita T, Matsuda T, Baba A. Cloning and characterization of the mouse pituitary adenylate cyclase-activating polypeptide (PACAP) gene. Gene211:63–69, 1998.
65.
Park JI, Kim WJ, Wang L, Park HJ, Lee J, Park JH, Kwon HB, Tsafriri A, Chun SY. Involvement of progesterone in gonadotrophin-induced pituitary adenylate cyclase-activating polypeptide gene expression in preovulatory follicles of rat ovary. Mol Hum Reprod6:238–245, 2000.
66.
Heraud C, Hilairet S, Muller JM, Leterrier JF, Chadeneau C. Neuritogenesis induced by vasoactive intestinal peptide, pituitary adenylate cyclase-activating polypeptide, and peptide histidine methionine in SH-SY5y cells is associated with regulated expression of cytoskeleton mRNAs and proteins. J Neurosci Res75:320–329, 2004.
67.
Vaudry D, Chen Y, Ravni A, Hamelink C, Elkahloun AG, Eiden LE. Analysis of the PC12 cell transcriptome after differentiation with pituitary adenylate cyclase-activating polypeptide (PACAP). J Neurochem83:1272–1284, 2002.
68.
Gonzalez BJ, Basille M, Vaudry D, Fournier A, Vaudry H. Pituitary adenylate cyclase-activating polypeptide promotes cell survival and neurite outgrowth in rat cerebellar neuroblasts. Neuroscience78:419–430, 1997.
69.
Cazillis M, Gonzalez BJ, Billardon C, Lombet A, Fraichard A, Samarut J, Gressens P, Vaudry H, Rostene W. VIP and PACAP induce selective neuronal differentiation of mouse embryonic stem cells. Eur J Neurosci19:798–808, 2004.
70.
Hashimoto H, Kunugi A, Arakawa N, Shintani N, Fujita T, Kasai A, Kawaguchi C, Morita Y, Hirose M, Sakai Y, Baba A. Possible involvement of a cyclic AMP-dependent mechanism in PACAP-induced proliferation and ERK activation in astrocytes. Biochem Biophys Res Commun311:337–343, 2003.
71.
Kultz D, Burg M. Evolution of osmotic stress signaling via MAP kinase cascades. J Exp Biol201:3015–3021, 1998.
72.
Matsumoto K, Wassarman KM, Wolffe AP. Nuclear history of a pre-mRNA determines the translational activity of cytoplasmic mRNA. EMBO J17:2107–2121, 1998.
73.
Gilks N, Kedersha N, Ayodele M, Shen L, Stoecklin G, Dember LM, Anderson P. Stress granule assembly is mediated by prion-like aggregation of TIA-1. Mol Biol Cell15:5383–5398, 2004.
74.
Moore MJ. From birth to death: the complex lives of eukaryotic mRNAs. Sci309:1514–1518, 2005.
75.
Lo M-J, Weng C-F. Developmental regulation of gastric pepsin and pancreatic serine protease in larvae of the euryhaline teleost, Oreochromis mossambicus. Aquaculture261:1403–1412, 2006.
