Li Fangfang, Li Dengfeng, Liu Huadie, Cao Bei-Bei, Jiang Fang, Chen Dan-Na, Li Jia-Da
Center for Medical Genetics, School of Life Sciences, Central South University, Changsha, China.
Hunan Key Laboratory of Animal Models for Human Diseases, Central South University, Changsha, China.
Front Endocrinol (Lausanne). 2019 Jan 24;10:12. doi: 10.3389/fendo.2019.00012. eCollection 2019.
, encoding an E3 ubiquitin ligase, has been identified as a causative gene for Gordon Holmes syndrome, characterized by ataxia, dementia, and hypogonadotropic hypogonadism. However, it is still elusive how deficiency in leads to hypogonadotropic hypogonadism. In this study, by using GN11 immature GnRH neuronal cell line, we demonstrated an important role of RNF216 in the GnRH neuron migration. RNA interference of RNF216 inhibited GN11 cell migration, but had no effect on the proliferation of GN11 cells or GnRH expression. Knockdown of RNF216 increased the protein levels of its targets, Arc and Beclin1. RNAi of Beclin1, but not Arc, normalized the suppressive effect caused by RNF216 knockdown. As Beclin1 plays a critical role in the autophagy regulation, we further demonstrated that RNAi of RNF216 led to increase in autophagy, and autophagy inhibitor CQ and 3-MA rescued the GN11 cell migration deficit caused by RNF216 knockdown. We further demonstrated that pharmacological increase autophagy by rapamycin could suppress the GN11 cell migration. We thus have identified that RNF216 regulates the migration of GnRH neuron by suppressing Beclin1 mediated autophagy, and indicated a potential contribution of autophagy to the hypogonadotropic hypogonadism.
编码一种E3泛素连接酶的基因已被确定为戈登·霍姆斯综合征的致病基因,该综合征的特征为共济失调、痴呆和低促性腺激素性性腺功能减退。然而,尚不清楚该基因的缺陷如何导致低促性腺激素性性腺功能减退。在本研究中,我们利用GN11未成熟促性腺激素释放激素(GnRH)神经元细胞系,证明了RNF216在GnRH神经元迁移中起重要作用。RNF216的RNA干扰抑制了GN11细胞的迁移,但对GN11细胞的增殖或GnRH表达没有影响。敲低RNF216会增加其靶标Arc和Beclin1的蛋白质水平。Beclin1的RNA干扰而非Arc的RNA干扰可使由RNF216敲低引起的抑制作用恢复正常。由于Beclin1在自噬调节中起关键作用,我们进一步证明RNF216的RNA干扰导致自噬增加,自噬抑制剂氯喹(CQ)和3-甲基腺嘌呤(3-MA)挽救了由RNF216敲低引起的GN11细胞迁移缺陷。我们进一步证明,雷帕霉素通过药理学方法增加自噬可抑制GN11细胞迁移。因此,我们确定RNF216通过抑制Beclin1介导的自噬来调节GnRH神经元的迁移,并表明自噬对低促性腺激素性性腺功能减退可能有影响。