Yuan Zhongmin, Mei Yuping, Zhou Jing, Tan Minghui, Song Bin, Ma Chi, Ying Chunyi, Li Dan, Ching Yick-Pang, Li Mingtao
Department of Pharmacology, Zhongshan School of Medicine, Sun Yat-sen University, 74 Zhongshan Road II, Guangzhou 510080, China.
Neurosci Lett. 2007 Sep 13;424(3):155-9. doi: 10.1016/j.neulet.2007.07.031. Epub 2007 Aug 3.
Cerebellar granule neurons (CGNs) undergo apoptosis when deprived of depolarizing concentration of potassium. A key regulator of cell cycle, E2F1, was believed to play a role in CGN apoptosis induced by potassium deprivation. However, here we demonstrated that although E2F1 was upregulated in wild type CGNs following potassium deprivation, CGNs that derived from E2F1 knockout mice underwent apoptosis at a similar rate as the wild type. Analysis of the apoptotic neurons revealed no difference in the activation of caspase-3 in E2F1 null and wild type CGNs. Furthermore, knockdown of E2F1 expression by RNA interference failed to attenuate the apoptosis of CGNs induced by potassium deprivation. Taken together, our results suggested that E2F1 is not essential for apoptosis induced by potassium deprivation in CGNs.
小脑颗粒神经元(CGNs)在缺乏去极化浓度的钾时会发生凋亡。细胞周期的关键调节因子E2F1被认为在钾缺乏诱导的CGN凋亡中起作用。然而,我们在此证明,尽管在钾缺乏后野生型CGNs中E2F1上调,但源自E2F1基因敲除小鼠的CGNs与野生型以相似的速率发生凋亡。对凋亡神经元的分析显示,E2F1缺失型和野生型CGNs中caspase-3的激活没有差异。此外,通过RNA干扰敲低E2F1表达未能减弱钾缺乏诱导的CGNs凋亡。综上所述,我们的结果表明E2F1对于CGNs中钾缺乏诱导的凋亡并非必不可少。