title: Neuropeptide B in Nile tilapia Oreochromis niloticus: molecular cloning and its effects on the regulation of food intake and mRNA expression of growth hormone and prolactin.
abstract: Neuropeptide B (NPB) regulates food intake, energy homeostasis and hormone secretion in mammals via two G-protein coupled receptors, termed as GPR 7 and GPR 8. However, there is no study that reports the function of NPB in teleosts. In this study, the full-length cDNA of prepro-NPB with the size of 663bp was cloned from the hypothalamus of Nile tilapia. The CDS of the prepro-NPB is 387bp which encodes a precursor protein with the size of 128a.a. This precursor contains a mature peptide with the size of 29a.a, and it was named as NPB29. Tissue distribution study showed that this gene was mainly expressed in different parts of brain, especially in the diencephalon as well as hypothalamus, and the spinal cord in Nile tilapia. Fasting significantly stimulated the mRNA expression of NPB in the brain area without hypothalamus, and refeeding after fasting for 3 and 14days also showed similar effects on NPB expression. While, only short-term fasting (3days) and refeeding after fasting for 7 and 14days induced mRNA expression of NPB in the hypothalamus. Intraperitoneal (i.p.) injection of NPB remarkably elevated the mRNA expression of hypothalamic neuropeptide Y (NPY), cholecystokinin 1 (CCK1) and pituitary prolactin (PRL), whereas significantly inhibited growth hormone (GH) expression in pituitary. These observations in the present study suggested that NPB may participate in the regulation of feeding and gene expression of pituitary GH and PRL in Nile tilapia.
authors.affiliation: State Key Laboratory of Biocontrol, Institute of Aquatic Economic Animals and Guangdong Provincial Key Laboratory for Aquatic Economic Animals, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, PR China.
authors.forename: Lu
authors.initials: L
authors.lastname: Yang
authors.affiliation: State Key Laboratory of Biocontrol, Institute of Aquatic Economic Animals and Guangdong Provincial Key Laboratory for Aquatic Economic Animals, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, PR China.
authors.forename: Caiyun
authors.initials: C
authors.lastname: Sun
authors.affiliation: State Key Laboratory of Biocontrol, Institute of Aquatic Economic Animals and Guangdong Provincial Key Laboratory for Aquatic Economic Animals, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, PR China. Electronic address: lsslws@mail.sysu.edu.cn.
authors.forename: Wensheng
authors.initials: W
authors.lastname: Li
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002766:Cholecystokinin / Q000235:genetics / Q000378:metabolism; D023681:Cichlids / Q000235:genetics*; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000378:metabolism; D004435:Eating / Q000187:drug effects / Q000235:genetics*; D005215:Fasting / Q000502:physiology; D029941:Fish Proteins / Q000235:genetics / Q000378:metabolism; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation / Q000187:drug effects*; D013006:Growth Hormone / Q000235:genetics* / Q000378:metabolism; D007031:Hypothalamus / Q000187:drug effects / Q000378:metabolism; D007274:Injections, Intraperitoneal; D008969:Molecular Sequence Data; D009478:Neuropeptide Y / Q000235:genetics / Q000378:metabolism; D009479:Neuropeptides / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D009928:Organ Specificity / Q000187:drug effects / Q000235:genetics; D010902:Pituitary Gland / Q000187:drug effects / Q000378:metabolism; D011388:Prolactin / Q000235:genetics* / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism
chemical_list: D018076:DNA, Complementary; D029941:Fish Proteins; D009478:Neuropeptide Y; D009479:Neuropeptides; D012333:RNA, Messenger; C495188:neuropeptide B; D011388:Prolactin; D013006:Growth Hormone; D002766:Cholecystokinin
keywords: Food intake; Growth hormone; Neuropeptide B; Nile tilapia; Prolactin; mRNA expression