title: Cloning and differential expression pattern of pituitary adenylyl cyclase-activating polypeptide and the PACAP-specific receptor in darkbarbel catfish Pelteobagrus vachelli.
abstract: Pituitary adenylyl cyclase-activating polypeptide (PACAP) can mediate growth hormone and gonadotropin release in teleost pituitary via PACAP receptors. In this study, the full-length cDNAs encoding PACAP and PACAP-related peptide (PRP) and the PACAP-specific receptor (PAC1-R) were cloned from the brain of darkbarbel catfish Pelteobagrus vachelli. The PRP-PACAP cDNA had two variants expressed by alternative splicing: a long form encoding both PRP and PACAP and a short form encoding PACAP only. Our data showed that the exon skipping on the PACAP transcripts was a possible mechanism regulating the expression ratio of PACAP to PRP in non-mammalian vertebrates. Based on multi-sequence alignments and phylogenetic analysis, the catfish PACAP and PAC1-R were highly conserved during evolution. Real-time quantitative PCR revealed that the PACAP-short and PAC1-R tanscripts were mainly expressed in the brain and gonad of darkbarbel catfish, though a small amount of mRNAs was also found in other tissues. Immunofluorescent staining studies showed wide distribution and high levels of PAC1-R in the catfish brain, suggesting that the PAC1-R form may play a central role in growth hormone release. The expressions of PACAP and PAC1-R in gonads and the occurrence of PACAP-immunoreactive material in testis suggest that PACAP may act as a paracrine/autocrine factor for gonad development.
authors.affiliation: School of Life Science, East China Normal University, Shanghai 200062, China.
authors.forename: Minhua
authors.initials: M
authors.lastname: Xu
authors.forename: Lina
authors.initials: L
authors.lastname: Long
authors.forename: Liqiao
authors.initials: L
authors.lastname: Chen
authors.forename: Jianguang
authors.initials: J
authors.lastname: Qin
authors.forename: Long
authors.initials: L
authors.lastname: Zhang
authors.forename: Na
authors.initials: N
authors.lastname: Yu
authors.forename: Erchao
authors.initials: E
authors.lastname: Li
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002397:Catfishes / Q000235:genetics*; D003001:Cloning, Molecular; D005260:Female; D005455:Fluorescent Antibody Technique; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation; D008297:Male; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000737:chemistry / Q000235:genetics*; D010802:Phylogeny; D051219:Pituitary Adenylate Cyclase-Activating Polypeptide / Q000737:chemistry / Q000235:genetics*; D011498:Protein Precursors / Q000737:chemistry / Q000235:genetics*; D012326:RNA Splicing / Q000235:genetics; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D051236:Receptors, Pituitary Adenylate Cyclase-Activating Polypeptide / Q000737:chemistry / Q000235:genetics*; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA
chemical_list: C108999:PACAP-related peptide; D010446:Peptide Fragments; D051219:Pituitary Adenylate Cyclase-Activating Polypeptide; D011498:Protein Precursors; D012333:RNA, Messenger; D051236:Receptors, Pituitary Adenylate Cyclase-Activating Polypeptide