title: Identification and characterization of kiss2 and kissr2 homologs in Paralichthys olivaceus.
abstract: The role of kisspeptin in puberty onset has been extensively investigated by neuroendocrinologists in the past decade. In the present study, we first cloned and analyzed Pokiss2 and Pokissr2 genes in Paralichthys olivaceus, a Pleuronectiformes fish. By 5'/3' rapid amplification of cDNA ends (RACE), the P. olivaceus kiss2 gene (Pokiss2) and two isoforms of the P. olivaceus kissr2 gene (Pokissr2) transcripts were cloned. During development, Pokissr2 was maternally inherited but Pokiss2 was not, and their expression reached maximum and minimum levels, respectively, when the gonads began to develop. Analysis of tissue distribution revealed that Pokiss2 and Pokissr2 transcripts were predominantly expressed in the brain and gonads, with expression levels in females higher than those in males. Moreover, Pokiss2 and Pokissr2 both showed significantly higher expression in brains and gonads during puberty. In situ hybridization of the ovary at pre-vitellogenesis stage and testis at spermatogonial proliferation stage revealed that both Pokiss2 and Pokissr2 were expressed in spermatocyte, oocytes, and some somatic cells. Our results also showed significantly stronger Pokiss2 expression in the area of the third ventricle of females than males and no Pokissr2 expression in this region in both sexes. These results lay a strong foundation for understanding the role of kisspeptin in neuroendocrine system in teleosts, in particular in Pleuronectiformes.
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: Haiyang
authors.initials: H
authors.lastname: Yu
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. zgwang@ouc.edu.cn.
authors.forename: Zhigang
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. qzhang@ouc.edu.cn.
authors.forename: Quanqi
authors.initials: Q
authors.lastname: Zhang
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D001921:Brain / Q000378:metabolism; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics; D005260:Female; D029941:Fish Proteins / Q000235:genetics*; D005432:Flounder / Q000235:genetics*; D059648:Kisspeptins / Q000235:genetics*; D008297:Male; D009865:Oocytes / Q000378:metabolism; D010053:Ovary / Q000378:metabolism; D010802:Phylogeny; D012333:RNA, Messenger / Q000378:metabolism; D043562:Receptors, G-Protein-Coupled / Q000235:genetics*; D012741:Sexual Maturation / Q000235:genetics; D013090:Spermatocytes / Q000378:metabolism; D013737:Testis / Q000378:metabolism
chemical_list: D018076:DNA, Complementary; D029941:Fish Proteins; D059648:Kisspeptins; D012333:RNA, Messenger; D043562:Receptors, G-Protein-Coupled
keywords: Brain; Gonad development; In situ hybridization; Kisspeptin; Paralichthys olivaceus