Guangdong Research Center on Reproductive Control and Breeding Technology of Indigenous Valuable Fish Species, Fisheries College, Guangdong Ocean University, Zhanjiang 524088, China.
Key Laboratory for Aquatic Economic Animals, School of Life Science, Sun Yet-sen University, Guangzhou 510000, China.
Comp Biochem Physiol B Biochem Mol Biol. 2020 Dec;250:110492. doi: 10.1016/j.cbpb.2020.110492. Epub 2020 Sep 2.
Growth hormone (GH) is the most important endocrine factor to regulate somatic growth. Spotted scat (Scatophagus argus) is a famous marine aquaculture species in China with a typical sexual growth dimorphism in which females grow faster and larger than males. In this study, gh messenger RNA (gh mRNA) and GH protein expression were examined in the pituitary glands of female and male spotted scat. Based on qPCR analysis, gh mRNA was mainly expressed in the pituitary gland, and weakly in the gonads and hypothalamus. Furthermore, gh mRNA expression in the pituitary gland was significantly higher in females at stages II-IV than in males at stages III-V. In addition, gh mRNA was highly expressed in the ovary and testis during mature development stages. In this study, spotted scat GH polyclonal antibody was produced. Western blot analysis showed that the molecular weight of spotted scat GH was about 21 KDa. Immunohistochemistry (IHC) in pituitary glands showed that GH was mainly expressed in the proximal pars distal (PPD) and a few cells were distributed in the rostral pairs distal (RPD). After injecting 17β-Estradiol (E) in vivo, gh mRNA expression was significantly up-regulated in the pituitary gland, whereas igf1 and ghr1 mRNA levels were down-regulated in the liver, which might regulate gh mRNA expression in the pituitary gland. These results provide valuable insight into the molecular mechanisms of E regulating gh expression in spotted scat.
生长激素（GH）是调节躯体生长的最重要的内分泌因子。斑点鲷（Scatophagus argus）是中国著名的海水养殖品种，具有典型的性生长二态性，即雌性生长速度和体型大于雄性。在这项研究中，我们检测了雌性和雄性斑点鲷垂体中的 gh 信使 RNA（gh mRNA）和 GH 蛋白表达。基于 qPCR 分析，gh mRNA 主要在垂体中表达，在性腺和下丘脑中有微弱表达。此外，在第二至第四阶段的雌性中，垂体中的 gh mRNA 表达明显高于在第三至第五阶段的雄性。此外，gh mRNA 在卵巢和睾丸的成熟发育阶段高度表达。在本研究中，制备了斑点鲷 GH 多克隆抗体。Western blot 分析表明，斑点鲷 GH 的分子量约为 21 kDa。垂体中的免疫组织化学（IHC）显示，GH 主要表达在近侧部远侧（PPD），少数细胞分布在远侧对部（RPD）。体内注射 17β-雌二醇（E）后，垂体中的 gh mRNA 表达显著上调，而肝脏中的 igf1 和 ghr1 mRNA 水平下调，这可能调节了垂体中的 gh mRNA 表达。这些结果为 E 调节斑点鲷 gh 表达的分子机制提供了有价值的见解。
