摘要
生长激素(growth hormone,GH)-胰岛素样生长因子(insulin-like growth,IGF)轴是调控鱼类生长的主要内分泌轴线.为探讨生长激素受体(growth hormone receptor,GHR)在斑鳢(Channa maculata)雌、雄生长差异中的调控机制,本研究克隆了斑鳢ghr基因序列,分析了基因结构,解析了ghr在成鱼不同组织和不同发育时期肝脏中的表达模式及其对外源性类固醇激素刺激的响应表达.结果表明,斑鳢ghr基因cDNA序列全长2 602 bp,包括100 bp 5'-UTR,1 872 bp开放阅读框,编码623个氨基酸,630 bp 3'-UTR.斑鳢ghr基因组序列长18 118 bp,包含9个外显子和8个内含子,在5'-端上游鉴定到899 bp的侧翼序列,经分析发现,ghr 5'-端侧翼序列含有雄激素受体(androgen receptor,AR)、含溴结构域蛋白4(bromodomain-containing protein 4,BRD4)和抑制元素-1-沉默转录因子(repressor element-1-silencing transcription factor,REST)等多种转录因子结合位点.成鱼组织表达分析证实ghr在斑鳢肝脏中高表达,且在雄性中的表达极显著高于雌性(P＜0.01);不同发育时期表达分析表明,ghr基因在365 d的雄性斑鳢肝脏中表达量最高,且极显著高于同时期雌性斑鳢(P＜0.01).激素诱导实验显示,长期注射17α-乙炔基雌二醇(17α-ethynylestradiol,EE2)会抑制雌、雄斑鳢 ghr 基因的表达;长期注射 17α-甲基睾丸酮(17α-methyltestosterone,MT)会抑制雌性斑鳢ghr的表达,但在一定时间内会促进雄性斑鳢ghr的表达.以上结果表明,GHR可能在斑鳢雌雄生长二态性中发挥作用,其表达受性类固醇激素调控,本研究为进一步探究GHR调控斑鳢生长发育的分子机理研究提供参考.
Abstract
The growth hormone(GH)-insulin-like growth factor(IGF)axis is the main endocrine axis that regulates fish growth.In order to explore the regulatory mechanism of growth hormone receptor(GHR)in the growth difference between female and male blotched snakehead(Channa maculata),the ghr gene in C.maculata was cloned,gene structure was analyzed,and the expression patterns of ghr in different adult tissues and liver at different developmental stages were clarified,meanwhile,its response to exogenous sex steroid hormones were also analyzed.The results showed that 2 602 bp cDNA sequence of the ghr gene in C.maculata was obtained,including 100 bp 5'-UTR,1 872 bp ORF,encoding 623 amino acids,and 630 bp 3'-UTR.The genome sequence of ghr gene in C.maculata was 18 118 bp long,including 9 exons and 8 introns.899 bp 5'-flanking sequence was identified,which contained androgen receptor(AR),bromomain-containing protein 4(BRD4)and suppressor element-1-silencing transcription factor(REST)and other transcription factor binding sites.ghr was highly expressed in the liver of adult C.maculata,and its expression in males was significantly higher than that in females(P＜0.01).The expression analysis of ghr gene at different developmental stages displayed that the highest expression of ghr gene was found in the liver of 365 d male C.maculata,which was significantly higher than that in females at the same period(P＜0.01).Hormone induction experiments showed that long-term injection of 17α-ethynylestradiol(EE2)inhibited ghr expression in male and female C.maculata,long-term injection of 17α-methyltestosterone(MT)inhibited ghr expression in female C.maculata,but promoted ghr expression in males within a certain period of time.The results demonstrate that GHR might play a key role in the growth difference between females and males and it is also regulated by sex steroid hormones in C.maculata.This study provides the reference for further exploring the molecular mechanism of growth regulation in blotched snakehead.
基金项目
现代农业产业技术体系建设项目(CARS-46)
国家自然科学基金面上项目(32373127)
广东省基础与应用基础研究基金(2021A1515012075)
广州市科技计划(202201010120)
中国水产科学研究院基本科研业务费专项(2023XT0202)
中国水产科学研究院基本科研业务费专项(2023TD37)
广东省淡水水产种质资源库运行项目(2022-SBH-00-001)
国家科技期刊平台
NSTL
万方数据