Dissecting GHRH- and pituitary adenylate cyclase activating polypeptide-mediated signalling in Xenopus.
The highly conserved neuropeptide pituitary adenylate cyclase activating polypeptide (PACAP) has been implicated in a broad variety of physiological processes. The PACAP precursor protein gives rise to three different peptides, the cryptic peptide, GHRH, and PACAP, respectively, and here we dissect their functional properties using Xenopus as model system. PACAP and GHRH but not the cryptic peptide directly neuralize animal caps. In contrast to GHRH, the neuralizing effect mediated by PACAP is independent of the PKA pathway. Moreover, PACAP but not GHRH behaves like a BMP-4 antagonist. Blastocoel injection of PACAP-38 but not of the closely related peptides PACAP-27 and VIP leads to strong anteriorization of the injected embryos suggesting the possible involvement of a novel PACAP-preferring receptor.
Otto
C
C
Molecular Biology of the Cell, German Cancer Research Center, Im Neuenheimer Feld 280, Heidelberg, Germany.
Schütz
G
G
Niehrs
C
C
Glinka
A
A
D000818:Animals; D055415:Bone Morphogenetic Protein 4; D019485:Bone Morphogenetic Proteins / Q000378:metabolism; D003001:Cloning, Molecular; D004625:Embryo, Nonmammalian / Q000378:metabolism / Q000528:radiation effects; D018507:Gene Expression Regulation, Developmental; D006023:Glycoproteins / Q000235:genetics / Q000378:metabolism; D007987:Gonadotropin-Releasing Hormone / Q000378:metabolism*; D036341:Intercellular Signaling Peptides and Proteins; D008845:Microinjections; D009479:Neuropeptides / Q000235:genetics* / Q000378:metabolism*; D051219:Pituitary Adenylate Cyclase-Activating Polypeptide; D011506:Proteins / Q000235:genetics / Q000378:metabolism; D011518:Proto-Oncogene Proteins / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction; D014660:Vasoactive Intestinal Peptide / Q000235:genetics / Q000378:metabolism; D051153:Wnt Proteins; D014981:Xenopus / Q000196:embryology* / Q000378:metabolism; D029867:Xenopus Proteins; D029961:Zebrafish Proteins
C495404:ADCYAP1 protein, Xenopus; D055415:Bone Morphogenetic Protein 4; D019485:Bone Morphogenetic Proteins; D006023:Glycoproteins; D036341:Intercellular Signaling Peptides and Proteins; D009479:Neuropeptides; D051219:Pituitary Adenylate Cyclase-Activating Polypeptide; D011506:Proteins; D011518:Proto-Oncogene Proteins; D051153:Wnt Proteins; D029867:Xenopus Proteins; D029961:Zebrafish Proteins; C525812:bmp4 protein, Xenopus; C525813:bmp4 protein, zebrafish; C109976:szl protein, Xenopus; D007987:Gonadotropin-Releasing Hormone; D014660:Vasoactive Intestinal Peptide; C054234:chordin