title: Identification of the receptors for somatostatin (SST) and cortistatin (CST) in chickens and investigation of the roles of cSST28, cSST14, and cCST14 in inhibiting cGHRH1-27NH2-induced growth hormone secretion in cultured chicken pituitary cells.
abstract: Somatostatin receptors (SSTRs) are proposed to mediate the actions of somatostatin (SST) and its related peptide, cortistatin (CST), in vertebrates. However, the identity, functionality, and tissue expression of these receptors remain largely unknown in most non-mammalian vertebrates including birds. In this study, five SSTRs (named cSSTR1, cSSTR2, cSSTR3, cSSTR4, cSSTR5) were cloned from chicken brain by RT-PCR. Using a pGL3-CRE-luciferase reporter system, we demonstrated that activation of each cSSTR expressed in CHO cells by cSST28, cSST14 and cCST14 treatment could inhibit forskolin-induced luciferase activity of CHO cells, indicating the functional coupling of all cSSTRs to Gi protein(s). Interestingly, cSSTR1-4 expressed in CHO cells could be activated by cSST28, cSST14 and cCST14 with high potencies, suggesting that they may function as the receptors common for these peptides. In contrast, cSSTR5 could be potently activated by cSST28 only, indicating that it is a cSST28-specific receptor. Using RT-PCR, wide expression of cSSTRs was detected in chicken tissues including pituitary. In accordance with their expression in pituitary, cSST28, cSST14, and cCST14 were demonstrated to inhibit basal and novel cGHRH1-27NH2-induced GH secretion in cultured chicken pituitary cells dose-dependently (0-10nM) by Western blot analysis, suggesting the involvement of cSSTR(s) common for these peptides in mediating their inhibitory actions. Collectively, our study establishes a molecular basis to elucidate the roles of SST/CST in birds and provide insights into the roles of SST/CST in vertebrates, such as their conserved actions on pituitary.
authors.affiliation: Key Laboratory of Bio-Resources and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu 610065, PR China.
authors.forename: Fengyan
authors.initials: F
authors.lastname: Meng
authors.affiliation: Key Laboratory of Bio-Resources and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu 610065, PR China.
authors.forename: Guian
authors.initials: G
authors.lastname: Huang
authors.affiliation: Key Laboratory of Bio-Resources and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu 610065, PR China.
authors.forename: Shunyu
authors.initials: S
authors.lastname: Gao
authors.affiliation: Key Laboratory of Bio-Resources and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu 610065, PR China.
authors.forename: Juan
authors.initials: J
authors.lastname: Li
authors.affiliation: Key Laboratory of Bio-Resources and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu 610065, PR China.
authors.forename: Zhenxin
authors.initials: Z
authors.lastname: Yan
authors.affiliation: Key Laboratory of Bio-Resources and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu 610065, PR China. Electronic address: cdwyjhk@gmail.com.
authors.forename: Yajun
authors.initials: Y
authors.lastname: Wang
mesh_terms: D000818:Animals; D016466:CHO Cells; D002478:Cells, Cultured; D002645:Chickens / Q000235:genetics* / Q000378:metabolism; D003412:Cricetulus; D005786:Gene Expression Regulation; D017930:Genes, Reporter; D013006:Growth Hormone / Q000037:antagonists & inhibitors / Q000378:metabolism*; D013007:Growth Hormone-Releasing Hormone / Q000494:pharmacology; D008156:Luciferases / Q000235:genetics / Q000378:metabolism; D009479:Neuropeptides / Q000235:genetics* / Q000378:metabolism / Q000494:pharmacology; D020033:Protein Isoforms / Q000235:genetics / Q000378:metabolism; D017481:Receptors, Somatostatin / Q000235:genetics* / Q000378:metabolism; D013004:Somatostatin / Q000235:genetics* / Q000378:metabolism / Q000494:pharmacology; D052683:Somatotrophs / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D014162:Transfection
chemical_list: D009479:Neuropeptides; D020033:Protein Isoforms; D017481:Receptors, Somatostatin; C099323:cortistatin; D013004:Somatostatin; D013006:Growth Hormone; D013007:Growth Hormone-Releasing Hormone; D008156:Luciferases
keywords: CST; Chicken; Pituitary growth hormone; SST; SSTR