关键词: 斜带石斑鱼, nesfatin-1, 组织分布, 生殖调控, Epinephelus coioides, nesfatin-1, tissue distribution, reproductive regulation

Abstract: Nesfatin - 1 is the hypothalamus gene encoding nuclear protein - 2 (nucleobindin - 2, NUCB2) produces a neuropeptide after cracking. Studies have shown that nesfatin - 1 play an important role in reproductive regulation, in order to study the Nesfatin - 1 relation with Epinephelus coioides reproductive regulation, in this paper, we have cloned two NUCB2 (NUCB2a and NUCB2b) gene, analyzes NUCB2 coding protein get sequence of amino acids about two nesfatin - 1 (nesfatin - 1a and nesfatin– 1b), at the same time, we analysis of the two kinds of nesfatin– 1's signal peptide and mature peptide, found it is consistent with that of vertebrates. Through real-time quantitative PCR technology, we determined the mRNA expression level of Epinepheluscoioidesnesfatin-1 in different tissues. The expression patterns revealed that, nesfatin-1a and nesfatin-1b widely expressed in the brain tissue, especially nesfatin - 1b abundantly expressed in the pituitary, also has the corresponding expression in the gonads. We determined thenesfatin-1 mRNA expression level of hypothalamus during ovary development, the result reveal that, nesfatin - 1a and nesfatin– 1b in the ovaries Ⅵ period (degradation of yolk formation stage oocytes) significantly increased, showed that two kinds of nesfatin - 1 are likely to participate in the regulation of ovarian mature. The intraperitoneal injection experiment results show that, injecting nesfatin - 1a and nesfatin – 1b 15 min, both GnRH1 and GnRH3 mRNA expression level of the hypothalamus are reduce, but in the pituitary LH –βand FSH – βmRNA expression level has not changed. Injection of nesfatin - 1a and nesfatin – 1b 60 min, the mRNA expression level of the hypothalamus GnRH1 and GnRH3 still suppressed. Injected nesfatin - 1a and nesfatin – 1b after 60 min, there have no effect change on the expression level of LH - β, but significantly reduced the expression of FSH -β. Through the above study shows nesfatin - 1a and nesfatin– 1b involved in Epinephelus coioides reproductive regulation.