Glia maturation factor overexpression in neuroblastoma cells activates glycogen synthase kinase-3beta and caspase-3.
Glia maturation factor overexpression in neuroblastoma cells activates glycogen synthase kinase-3beta and caspase-3.
复制标题
神经母细胞瘤细胞中神经胶质成熟因子的过度表达会激活糖原合酶激酶 3beta 和 caspase-3。
DOI：
10.1016/j.brainres.2007.11.011
复制
发表时间：
2008
期刊：
影响因子：
2.9
通讯作者：
Yang,Baoli
中科院分区：
文献类型：
--
作者：
Zaheer,Asgar;Knight,Scott;Zaheer,Ashna;Ahrens,Marcus;Sahu,ShailendraK;Yang,Baoli
在本研究中，我们报道了GMF cDNA复制缺陷腺病毒（GMF- v）在神经母细胞瘤（N18）细胞中诱导GMF蛋白过表达，导致细胞毒性和细胞活力丧失。与模拟对照组和lacZ对照组相比，GMF-V感染后GSK-3β的活化显著增加。GMF的过表达也增加了caspase-3的活性，caspase-3是细胞凋亡的早期标志。通过引入GMF特异性siRNA （GsiRNA）来消耗GMF基因完全阻断了GSK-3β和caspase-3的激活，而对照siRNA （CsiRNA）则没有影响。GSK-3β的细胞渗透性肽抑制剂和锂完全阻止了gmf依赖性caspase-3的激活。这些结果表明GSK-3通过GMF过表达介导死亡结构域caspase的激活。我们还发现，在N18细胞中，gsk -3依赖性Tau位点的磷酸化是gmf过表达的结果。综上所述，我们的研究结果表明，GMF参与了导致N18细胞中GSK-3β和caspase-3激活的信号传导，并强烈提示其参与神经退行性变，因为GSK-3β已知会使tau过度磷酸化，而tau与阿尔茨海默病中神经原纤维缠结的神经毒性有关。
In the present study we report that a replication-defective adenovirus construct of GMF cDNA (GMF-V) induced overexpression of GMF protein in neuroblastoma (N18) cells caused cytotoxicity and loss of cell viability. A significant increase in activation of GSK-3β occurred after infection with GMF-V when compared with mock and lacZ controls. Overexpression of GMF also increased caspase-3 activity, an early marker of apoptosis. Depletion of GMF gene by introducing GMF-specific siRNA (GsiRNA) completely blocked both activation of GSK-3β and caspase-3 activation whereas a control scrambled siRNA (CsiRNA) had no effect. A cell-permeable peptide inhibitor of GSK-3β, and lithium completely prevented GMF-dependent activation of caspase-3. These results demonstrate that GSK-3 mediates activation of the death domain caspase by GMF overexpression. We also show that the phosphorylation of GSK-3-dependent site of Tau was a consequence of GMF-overexpression in N18 cells. Taken together our results imply that GMF is involved in the signaling leading to the activation of GSK-3β and caspase-3 in N18 cells and strongly suggest its involvement in neurodegeneration since GSK-3β is known to hyperphosphorylate tau which is associated with the neurotoxicity of neurofibrillary tangles in Alzheimer's disease.