title: Characterization of kiss2 and kissr2 genes and the regulation of kisspeptin on the HPG axis in Cynoglossus semilaevis.
abstract: Reproduction allows organisms to produce offspring. Animals shift from immature juveniles into mature adults and become capable of sexual reproduction during puberty, which culminates in the first spermiation and sperm hydration or ovulation. Reproduction is closely related to the precise control of the hypothalamic-pituitary-gonadal (HPG) axis. Kisspeptin peptides are considered as the important regulator of HPG axis in mammalian. However, the current understanding of kisspeptin in flatfish is not comprehensive. In this study, we cloned and analyzed the kiss2 and kissr2 genes in Cynoglossus semilaevis. Interesting alternative splicing in the 5'-untranslated regions (UTR) of the Cskissr2 gene was found. The expression profiles of Cskiss2 and Cskissr2 showed relative high messenger RNA (mRNA) levels at the late gastrula stage during embryonic development, at total length = 40 mm during early gonadal differentiation, and in the brains and gonads of all investigated tissues. These results suggested that the kisspeptin system participated in embryogenesis and in the regulation of gonadal differentiation and development. Considering that the control and regulatory mechanisms of kisspeptin in the central reproductive axis are still unclear, we documented that the intramuscular injection of kisspeptin caused different sGnRH and cGnRH mRNA levels in a dose- and tissue-dependent manner. The mRNA expressions of FSH and LH were stimulated in the ovary and were inhibited in the testis under the kisspeptin treatments. These results provided foundations for understanding the roles of kisspeptin in the neuroendocrine system in fish. The manipulation of the kisspeptin system may provide new opportunities to control the gonadal development and even reproduction in fish.
authors.affiliation: Key Laboratory of Marine Genetics and Breeding, Ministry of Education, College of Marine Life Sciences, Ocean University of China, Qingdao, 266003, People's Republic of China.
authors.forename: Huayu
authors.initials: H
authors.lastname: Song
authors.affiliation: Key Laboratory of Marine Genetics and Breeding, Ministry of Education, College of Marine Life Sciences, Ocean University of China, Qingdao, 266003, People's Republic of China.
authors.forename: Mengxun
authors.initials: M
authors.lastname: Wang
authors.affiliation: Key Laboratory of Marine Genetics and Breeding, Ministry of Education, College of Marine Life Sciences, Ocean University of China, Qingdao, 266003, People's Republic of China.
authors.forename: Zhongkai
authors.initials: Z
authors.lastname: Wang
authors.affiliation: Key Laboratory of Marine Genetics and Breeding, Ministry of Education, College of Marine Life Sciences, Ocean University of China, Qingdao, 266003, People's Republic of China.
authors.forename: Jinxiang
authors.initials: J
authors.lastname: Liu
authors.affiliation: Key Laboratory of Marine Genetics and Breeding, Ministry of Education, College of Marine Life Sciences, Ocean University of China, Qingdao, 266003, People's Republic of China.
authors.forename: Jie
authors.initials: J
authors.lastname: Qi
authors.affiliation: Key Laboratory of Marine Genetics and Breeding, Ministry of Education, College of Marine Life Sciences, Ocean University of China, Qingdao, 266003, People's Republic of China. qzhang@ouc.edu.cn.
authors.forename: Quanqi
authors.initials: Q
authors.lastname: Zhang
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D003001:Cloning, Molecular; D004247:DNA; D029941:Fish Proteins / Q000235:genetics / Q000378:metabolism; D005412:Flatfishes / Q000235:genetics / Q000378:metabolism*; D005786:Gene Expression Regulation / Q000502:physiology*; D006066:Gonads / Q000502:physiology*; D007030:Hypothalamo-Hypophyseal System / Q000502:physiology*; D059648:Kisspeptins / Q000235:genetics / Q000378:metabolism*; D010802:Phylogeny; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D011994:Recombinant Proteins / Q000737:chemistry / Q000494:pharmacology
chemical_list: D029941:Fish Proteins; D059648:Kisspeptins; D012333:RNA, Messenger; D011994:Recombinant Proteins; D004247:DNA
keywords: Cynoglossus semilaevis; GnRH; Gonadal development; Kisspeptin administration; kiss2