Protein kinase CK2 phosphorylates BAD at threonine-117.
Reversible phosphorylation of the 22 kDa BAD protein is crucial for cell survival. Five phosphorylation sites, all serines, had been identified. Here we report on number six. It is threonine-117 phosphorylated by the constitutively active kinase, CK2. Phosphoamino acid analysis and phospho-specific antibodies confirmed Thr117 as additional phosphorylation site. Immunoprecipitation furthermore revealed that BAD is phosphorylated at Thr117 in cultured cortical neurons. PP1, PP2A and PP2C dephosphorylated BAD at Thr117, but PP2B did not. The discovery of the constitutively active CK2 phosphorylating BAD is shedding an unexpected light in the otherwise strictly signal-regulated phosphorylation events on BAD.
Klumpp
Susanne
S
Institut für Pharmazeutische & Medizinische Chemie, Westfälische Wilhelms-Universität, Hittorfstr. 58-62, D-48149 Münster, Germany. klumpp@uni-muenster.de
Mäurer
Anette
A
Zhu
Yuan
Y
Aichele
Dagmar
D
Pinna
Lorenzo A
LA
Krieglstein
Josef
J
D000255:Adenosine Triphosphate / Q000378:metabolism; D000818:Animals; D015153:Blotting, Western; D002352:Carrier Proteins / Q000378:metabolism*; D047390:Casein Kinase II; D002478:Cells, Cultured; D002540:Cerebral Cortex / Q000166:cytology / Q000378:metabolism; D017868:Cyclic AMP-Dependent Protein Kinases / Q000378:metabolism; D007202:Indicators and Reagents; D020929:Mitogen-Activated Protein Kinase Kinases / Q000378:metabolism; D009474:Neurons / Q000378:metabolism; D019606:Phosphoamino Acids / Q000378:metabolism; D010749:Phosphoprotein Phosphatases / Q000378:metabolism; D010766:Phosphorylation; D011233:Precipitin Tests; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism*; D011518:Proto-Oncogene Proteins / Q000378:metabolism; D051057:Proto-Oncogene Proteins c-akt; D051381:Rats; D013912:Threonine / Q000378:metabolism*; D051025:bcl-Associated Death Protein
C494821:Bad protein, rat; D002352:Carrier Proteins; D007202:Indicators and Reagents; D019606:Phosphoamino Acids; D011518:Proto-Oncogene Proteins; D051025:bcl-Associated Death Protein; D013912:Threonine; D000255:Adenosine Triphosphate; D047390:Casein Kinase II; D017346:Protein Serine-Threonine Kinases; D051057:Proto-Oncogene Proteins c-akt; D017868:Cyclic AMP-Dependent Protein Kinases; D020929:Mitogen-Activated Protein Kinase Kinases; D010749:Phosphoprotein Phosphatases