title: Identification of the receptors for prolactin-releasing peptide (PrRP) and Carassius RFamide peptide (C-RFa) in chickens.
abstract: Prolactin-releasing peptide (PrRP) and its structurally related peptide, Carassius Arg-Phe-amide peptide (C-RFa), have been reported to play similar roles in regulating food intake and pituitary functions in vertebrates. However, the identity, functionality, and expression of the receptor(s) for PrRP and C-RFa remain largely unknown in nonmammalian vertebrates, including birds. In this study, three receptors homologous to mammalian PrRP receptor (PrRPR), named cPrRPR1, cPrRPR2, and cC-RFaR, respectively, were cloned from chicken brain by RT-PCR. Using a pGL3-NFAT-RE-luciferase reporter system, we demonstrated that cPrRPR1 and cPrRPR2 expressed in Chinese hamster ovarian cells could be activated by cPrRP₂₀ and cC-RFa₂₀ potently, whereas cC-RFaR could only be activated effectively by cC-RFa₂₀ (EC₅₀, 0.11 nM), indicating that cPrRPR1 and cPrRPR2 can function as common receptors for PrRP and C-RFa, whereas cC-RFaR is a receptor specific to C-RFa. Using a pGL3-CRE-luciferase reporter system, cPrRPR1, cPrRPR2, and cC-RFaR expressed in Chinese hamster ovarian cells were also shown to activate intracellular protein kinase A signaling pathway upon cC-RFa₂₀ treatment (100 nM). Moreover, RT-PCR assay revealed that cPrRPR1, cPrRPR2, and cC-RFaR were widely expressed in most adult chicken tissues examined, including various regions of brain. These findings, together with evidence of PrRP and C-RFa encoded by separate genes in chicken, Xenopus, and zebrafish, and the differential expression of PrRP and C-RFa genes in chicken tissues, strongly suggest that PrRP and C-RFa may play similar yet distinctive roles in nonmammalian vertebrates, including chicken, and their actions are mediated by common receptor(s) or a specific C-RFa receptor.
authors.affiliation: Key Laboratory of Bio-resources and Eco-environment of Ministry of Education, School of Life Sciences, Sichuan University, Chengdu 610064, People's Republic of China. cdwyjhk@gmail.com
authors.forename: Yajun
authors.initials: Y
authors.lastname: Wang
authors.forename: Crystal Ying
authors.initials: CY
authors.lastname: Wang
authors.forename: Yuting
authors.initials: Y
authors.lastname: Wu
authors.forename: Guian
authors.initials: G
authors.lastname: Huang
authors.forename: Juan
authors.initials: J
authors.lastname: Li
authors.forename: Frederick C
authors.initials: FC
authors.lastname: Leung
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001921:Brain / Q000378:metabolism*; D002642:Chick Embryo; D002645:Chickens / Q000378:metabolism*; D002874:Chromosome Mapping; D017868:Cyclic AMP-Dependent Protein Kinases / Q000502:physiology; D018076:DNA, Complementary / Q000378:metabolism; D005786:Gene Expression Regulation; D006801:Humans; D051379:Mice; D008969:Molecular Sequence Data; D009479:Neuropeptides / Q000235:genetics* / Q000378:metabolism*; D051381:Rats; D018013:Receptors, Neuropeptide / Q000235:genetics* / Q000378:metabolism*; D015398:Signal Transduction / Q000502:physiology; D014981:Xenopus; D015027:Zebrafish
chemical_list: D018076:DNA, Complementary; D009479:Neuropeptides; C416987:RFamide peptide; D018013:Receptors, Neuropeptide; C400801:receptor, prolactin-releasing peptide; D017868:Cyclic AMP-Dependent Protein Kinases