title: Gene structure analysis of kisspeptin-2 (Kiss2) in the Senegalese sole (Solea senegalensis): characterization of two splice variants of Kiss2, and novel evidence for metabolic regulation of kisspeptin signaling in non-mammalian species.
abstract: Kisspeptin signaling in the brain is involved in the control of the onset of puberty in vertebrates. In this study, we present novel evidence indicating that kisspeptin may link energy balance and reproduction. For that purpose, we determined the complete gene structure of kisspeptin in a teleost fish, the Senegalese sole (Ss). In contrast to the situation evident in several fish, in this species only Kiss2 was found. Yet, two Ss Kiss2 isoforms generated by alternative splicing through intronic retention were detected: Ss Kiss2_v1, producing the functional protein, and Ss Kiss2_v2, coding for a truncated, non-functional protein. Specific qPCRs showed that the expression of these two isoforms varied differently in brain and gonads throughout maturation. In addition, and in contrast to what has been observed in mammals, fasting increased hypothalamic mRNA levels of Ss Kiss2_v1, which also caused a concomitant rise in pituitary Ss LH and Ss FSH mRNA. Together, these data indicate the impact of the nutritional status on Kiss mRNA expression as a potential regulatory mechanism for the metabolic control of reproduction in non-mammalian species, albeit with some significant differences with respect to the situation described in mammals.
authors: Institut de Ciències del Mar, Consejo Superior de Investigaciones Científicas (CSIC), Passeig Marítim, 37-49, 08003 Barcelona, Spain.
authors: Alejandro S
authors: AS
authors: Mechaly
authors: Jordi
authors: J
authors: Viñas
authors: Francesc
authors: F
authors: Piferrer
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D001921:Brain / Q000378:metabolism; D003001:Cloning, Molecular; D004734:Energy Metabolism / Q000235:genetics*; D005260:Female; D029941:Fish Proteins / Q000235:genetics* / Q000378:metabolism; D005412:Flatfishes / Q000235:genetics*; D005640:Follicle Stimulating Hormone / Q000235:genetics / Q000378:metabolism; D005508:Food Deprivation; D005753:Gastric Mucosa / Q000378:metabolism; D040461:Gene Components; D006066:Gonads / Q000033:anatomy & histology / Q000378:metabolism; D007031:Hypothalamus / Q000378:metabolism; D059648:Kisspeptins; D007986:Luteinizing Hormone / Q000235:genetics / Q000378:metabolism; D008297:Male; D008969:Molecular Sequence Data; D009929:Organ Size; D010802:Phylogeny; D010902:Pituitary Gland / Q000378:metabolism; D020033:Protein Isoforms / Q000235:genetics* / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics; D012098:Reproduction / Q000235:genetics; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D015398:Signal Transduction; D014158:Transcription, Genetic; D025521:Tumor Suppressor Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism
chemical_list: D029941:Fish Proteins; C106628:KISS1 protein, human; D059648:Kisspeptins; D020033:Protein Isoforms; D012333:RNA, Messenger; D025521:Tumor Suppressor Proteins; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone