Palevitch Ori, Abraham Eytan, Borodovsky Natalya, Levkowitz Gil, Zohar Yonathan, Gothilf Yoav
Department of Neurobiology, George S. Wise Faculty of Life Sciences, Tel-Aviv University, Tel Aviv, Israel.
Dev Dyn. 2009 Jan;238(1):66-75. doi: 10.1002/dvdy.21823.
The initiation of puberty and the functioning of the reproductive system depend on proper development of the hypophysiotropic gonadotropin-releasing hormone (GnRH) system. One critical step in this process is the embryonic migration of GnRH neurons from the olfactory area to the hypothalamus. Using a transgenic zebrafish model, Tg(gnrh3:EGFP), in which GnRH3 neurons and axons are fluorescently labeled, we investigated whether zebrafish NELF is essential for the development of GnRH3 neurons. The zebrafish nelf cDNA was cloned and characterized. During embryonic development, nelf is expressed in GnRH3 neurons and in target sites of GnRH3 projections and perikarya, before the initiation of their migration. Nelf knockdown resulted in a disruption of the GnRH3 system which included absence or misguiding of GnRH3 axonal outgrowth and incorrect or arrested migration of GnRH3 perikarya. These results suggest that Nelf is an important factor in the developmental migration and projection of GnRH3 neurons in zebrafish.
青春期的启动和生殖系统的功能依赖于促性腺激素释放激素（GnRH）下丘脑调节系统的正常发育。这一过程中的一个关键步骤是GnRH神经元从嗅觉区域向下丘脑的胚胎迁移。利用转基因斑马鱼模型Tg(gnrh3:EGFP)，其中GnRH3神经元和轴突被荧光标记，我们研究了斑马鱼NELF对于GnRH3神经元发育是否必不可少。克隆并鉴定了斑马鱼nelf cDNA。在胚胎发育过程中，nelf在GnRH3神经元以及GnRH3投射和核周体的靶位点表达，先于它们迁移的起始阶段。Nelf基因敲低导致GnRH3系统的破坏，包括GnRH3轴突生长缺失或导向错误以及GnRH3核周体迁移不正确或停滞。这些结果表明，Nelf是斑马鱼GnRH3神经元发育迁移和投射中的一个重要因素。
