dp5/HRK is a c-Jun target gene and required for apoptosis induced by potassium deprivation in cerebellar granule neurons.
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.
Ma
Chi
C
Department of Pharmacology, Zhongshan School of Medicine, Sun Yat-sen University, China.
Ying
Chunyi
C
Yuan
Zhongmin
Z
Song
Bin
B
Li
Dan
D
Liu
Yulin
Y
Lai
Bingquan
B
Li
Wenming
W
Chen
Ruzhu
R
Ching
Yick-Pang
YP
Li
Mingtao
M
D051698:Activating Transcription Factor 2 / Q000235:genetics / Q000378:metabolism; D000818:Animals; D017209:Apoptosis / Q000502:physiology*; D051017:Apoptosis Regulatory Proteins / Q000096:biosynthesis* / Q000235:genetics / Q000378:metabolism; D001483:Base Sequence / Q000235:genetics; D000072224:Bcl-2-Like Protein 11; D002478:Cells, Cultured; D002531:Cerebellum / Q000166:cytology / Q000378:metabolism*; D003594:Cytoplasmic Granules / Q000235:genetics / Q000378:metabolism; D053222:Fas Ligand Protein / Q000235:genetics / Q000378:metabolism; D005799:Genes, Dominant / Q000502:physiology; D016758:Genes, jun / Q000502:physiology*; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism; D009474:Neurons / Q000166:cytology / Q000378:metabolism*; D009479:Neuropeptides / Q000096:biosynthesis* / Q000235:genetics; D011188:Potassium / Q000378:metabolism*; D011518:Proto-Oncogene Proteins / Q000235:genetics / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D020218:Response Elements / Q000502:physiology; D017384:Sequence Deletion; D014158:Transcription, Genetic / Q000502:physiology; D015854:Up-Regulation / Q000502:physiology
D051698:Activating Transcription Factor 2; D051017:Apoptosis Regulatory Proteins; C497107:Atf2 protein, rat; D000072224:Bcl-2-Like Protein 11; C000606778:Bcl2l11 protein, rat; D053222:Fas Ligand Protein; C484585:Hrk protein, rat; D008565:Membrane Proteins; D009479:Neuropeptides; D011518:Proto-Oncogene Proteins; D011188:Potassium