dp5/HRK is a c-jun target gene and required for apoptosis induced by potassium deprivation in cerebellar granule neurons
dp5/HRK is a c-jun target gene and required for apoptosis induced by potassium deprivation in cerebellar granule neurons
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dp5/HRK 是 c-Jun 靶基因，是小脑颗粒神经元缺钾诱导细胞凋亡所必需的
DOI：
10.1074/jbc.m608694200
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发表时间：
2007-10-19
影响因子：
4.8
通讯作者：
Li, Mingtao
中科院分区：
文献类型：
--
作者：
Ma, Chi;Ying, Chunyi;Li, Mingtao
在小脑颗粒神经元中，在钾剥夺诱导的细胞凋亡过程中，仅BH 3的Bcl-2家族成员死亡蛋白5/harakiri以JNK依赖的方式上调。然而，目前尚不清楚c-Jun是否直接参与dp 5的诱导。在这里，我们发现dp 5的上调，而不是fas配体和bim，对dp 5基因5 '侧翼序列的缺失分析表明，在缺钾诱导过程中，一个主要的反应元件是位于-116至-118位的ATF结合位点，该位点位于-116至-118位，109相对于转录起始位点。该位点的突变完全消除了启动子激活。此外，凝胶迁移试验表明，一个特定的复合物含有c-Jun和ATF 2识别这个网站，并增加钾剥夺小脑颗粒神经元。染色质免疫沉淀表明，c-Jun能够结合到这个网站在体内。最后，我们证明，敲低Dp 5的小干扰RNA从钾剥夺诱导的细胞凋亡中拯救神经元。综上所述，这些结果表明，dp 5是c-Jun的靶基因，并在钾剥夺诱导的小脑颗粒神经元凋亡中起关键作用。
In cerebellar granule neurons, a BH3-only Bcl-2 family member, death protein 5/harakiri, is up-regulated in a JNK-dependent manner during apoptosis induced by potassium deprivation. However, it is not clear whether c-Jun is directly involved in the induction of dp5. Here, we showed that the up-regulation of dp5, but not fas ligand and bim, after potassium deprivation was suppressed by the expression of a dominant negative form of c-Jun. Deletion analysis of the 5 '-flanking sequence of the dp5 gene revealed that a major responsive element responsible for the induction by potassium deprivation is an ATF binding site located at -116 to -109 relative to the transcriptional start site. Mutation of this site completely abolished promoter activation. Furthermore, a gel shift assay showed that a specific complex containing c-Jun and ATF2 recognized this site and increased in potassium-deprived cerebellar granule neurons. Chromatin immunoprecipitation demonstrated that c-Jun was able to bind to this site in vivo. Finally, we demonstrated that knockdown of Dp5 by small interfering RNA rescued neurons from potassium deprivation-induced apoptosis. Taken together, these results suggest that dp5 is a target gene of c-Jun and plays a critical role in potassium deprivation-induced apoptosis in cerebellar granule neurons.