Wang Xueqian, Wang Xin, Yuan Wei, Chai Renjie, Liu Dong
Co-innovation Center of Neuroregeneration, Jiangsu Key Laboratory of Neuroregeneration, Nantong University, Qixiu Road 19, 226001, Nantong, China.
Fish Physiol Biochem. 2015 Aug;41(4):961-9. doi: 10.1007/s10695-015-0061-x. Epub 2015 May 8.
The epidermal growth factor (EGF) repeat motif defines a superfamily of diverse protein involved in regulating a variety of cellular and physiological processes, such as cell cycle, cell adhesion, proliferation, migration, and neural development. Egfl6, an EGF protein, also named MAGE was first cloned in human tissue. Up to date, the study of zebrafish Egfl6 expression pattern and functional analysis of Egfl6 involved in embryonic development of vertebrate in vivo is thus far lacking. Here we reported that Egfl6 was involved in zebrafish notochord development. It was shown that Egfl6 mRNA was expressed in zebrafish, developing somites, fin epidermis, pharyngeal arches, and hindbrain region. Particularly the secreted Egfl6 protein was significantly accumulated in notochord. Loss of Egfl6 function in zebrafish embryos resulted in curved body with distorted notochord in the posterior trunk. It was observed that expression of all Notch ligand and receptors in notochord of 28 hpf Egfl6 morphants was not affected, except notch2, which was up-regulated. We found that inhibition of Notch signaling by DAPT efficiently rescued notochord developmental defect of Egfl6 deficiency embryos.
表皮生长因子（EGF）重复基序定义了一个多样蛋白质的超家族，这些蛋白质参与调节多种细胞和生理过程，如细胞周期、细胞黏附、增殖、迁移和神经发育。Egfl6是一种EGF蛋白，也被称为MAGE，最初是在人体组织中克隆出来的。迄今为止，关于斑马鱼Egfl6表达模式以及其在脊椎动物胚胎发育中的功能分析的体内研究仍属空白。在此我们报道，Egfl6参与斑马鱼脊索发育。研究表明，Egfl6 mRNA在斑马鱼发育中的体节、鳍表皮、咽弓和后脑区域表达。特别地，分泌型Egfl6蛋白在脊索中显著积累。斑马鱼胚胎中Egfl6功能缺失导致身体弯曲，躯干后部脊索变形。我们观察到，在28 hpf的Egfl6 morphants的脊索中，除notch2上调外，所有Notch配体和受体的表达均未受影响。我们发现，用DAPT抑制Notch信号可有效挽救Egfl6缺陷胚胎的脊索发育缺陷。
