Li Shi-Zhu, Liu Wei, Li Zhi, Li Wen-Hua, Wang Yang, Zhou Li, Gui Jian-Fang
State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Graduate University of the Chinese Academy of Sciences, Wuhan 430072, China.
Guangdong Provincial Key Laboratory of Marine Resources and Coastal Engineering, Sun Yat-sen University, Guangzhou 510275, China.
Gene. 2017 Sep 5;627:176-187. doi: 10.1016/j.gene.2017.06.016. Epub 2017 Jun 9.
greb1, growth regulation by estrogen in breast cancer 1, is an important estrogen response gene, which participates in breast cancer formation. However, the role of greb1 in development is largely unknown. In this study, we have characterized greb1 expression patterns and revealed its regulative role in convergent extension movement and pituitary development in zebrafish. In zebrafish adults, greb1 was revealed to be expressed mainly in pituitary, hypothalamus, liver, and gonads. During embryogenesis, RT-PCR and WISH revealed its spatial and temporal expression specific to embryonic margin during gastrulation, central nervous system during segmentation and brain ventricular regions from 24hpf. To investigate its function, we utilized TALEN-mediated knockout strategy and obtained a greb1 mutant zebrafish line. greb1 mutation caused convergent extension (CE) movement defect and developmental delay during gastrulation, and resulted in significant growth defects in zebrafish adults. Moreover, four pituitary cells including somatotropes, thyrotropes, lactotropes and gonadotropes were specifically reduced during embryogenesis. Importantly, pituitary hormones-encoding genes and their serum products, such as GH, TSH, PRL, FSH, and LH, were severely diminished in greb1 mutants, and high mortality and significant growth defects were observed. Therefore, our present study indicates that greb1 is a novel regulator for CE movement and pituitary development in zebrafish.
GREB1（乳腺癌中雌激素调节的生长因子1）是一种重要的雌激素反应基因，参与乳腺癌的形成。然而，GREB1在发育过程中的作用尚不清楚。在本研究中，我们对GREB1的表达模式进行了表征，并揭示了其在斑马鱼汇聚延伸运动和垂体发育中的调节作用。在成年斑马鱼中，GREB1主要在垂体、下丘脑、肝脏和性腺中表达。在胚胎发育过程中，逆转录聚合酶链反应（RT-PCR）和原位杂交（WISH）显示，在原肠胚形成过程中，GREB1在胚胎边缘特异性表达，在体节形成过程中在中枢神经系统表达，在受精后24小时开始在脑室区域表达。为了研究其功能，我们采用了转录激活样效应因子核酸酶（TALEN）介导的基因敲除策略，获得了一条GREB1突变斑马鱼品系。GREB1突变导致原肠胚形成过程中汇聚延伸（CE）运动缺陷和发育延迟，并导致成年斑马鱼出现明显的生长缺陷。此外，在胚胎发育过程中，包括生长激素细胞、促甲状腺激素细胞、催乳素细胞和促性腺激素细胞在内的四种垂体细胞特异性减少。重要的是，GREB1突变体中垂体激素编码基因及其血清产物，如生长激素（GH）、促甲状腺激素（TSH）、催乳素（PRL）、促卵泡激素（FSH）和促黄体生成素（LH）显著减少，并观察到高死亡率和明显的生长缺陷。因此，我们目前的研究表明，GREB1是斑马鱼CE运动和垂体发育的一种新型调节因子。
