Casein kinase 2 interacts with cyclin-dependent kinase 11 (CDK11) in vivo and phosphorylates both the RNA polymerase II carboxyl-terminal domain and CDK11 in vitro.
The PITSLRE protein kinases, hereafter referred to as cyclin-dependent kinase 11 (CDK11) due to their association with cyclin L, are part of large molecular weight protein complexes that contain RNA polymerase II (RNAP II) as well as numerous transcription and RNA processing factors. Data presented here demonstrate that the influence of CDK11(p110) on transcription and splicing does not involve phosphorylation of the RNAP II carboxyl-terminal domain by CDK11(p110). We have isolated a DRB- and heparin-sensitive protein kinase activity that co-purifies with CDK11(p110) after ion exchange and affinity purification chromatography. This protein kinase was identified as casein kinase 2 (CK2) by immunoblot and mass spectrometry analyses. In addition to the RNAP II carboxyl-terminal domain, CK2 phosphorylates the CDK11(p110) amino-terminal domain. These data suggest that CDK11(p110) isoforms participate in signaling pathways that include CK2 and that its function may help to coordinate the regulation of RNA transcription and processing events. Future experiments will determine how phosphorylation of CDK11(p110) by CK2 specifically affects RNA transcription and/or processing events.
Trembley
Janeen H
JH
Department of Genetics and Tumor Cell Biology, St. Jude Children's Research Hospital, Memphis, Tennessee 38105, USA.
Hu
Dongli
D
Slaughter
Clive A
CA
Lahti
Jill M
JM
Kidd
Vincent J
VJ
D047390:Casein Kinase II; D002460:Cell Line; D018844:Cyclin-Dependent Kinases / Q000378:metabolism*; D017353:Gene Deletion; D005982:Glutathione Transferase / Q000378:metabolism; D006367:HeLa Cells; D006801:Humans; D015151:Immunoblotting; D013058:Mass Spectrometry; D008957:Models, Genetic; D010766:Phosphorylation; D011233:Precipitin Tests; D011485:Protein Binding; D020033:Protein Isoforms; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism*; D017434:Protein Structure, Tertiary; D012313:RNA / Q000378:metabolism; D012319:RNA Polymerase II / Q000737:chemistry* / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D011994:Recombinant Proteins / Q000378:metabolism; D014158:Transcription, Genetic; D014162:Transfection
D020033:Protein Isoforms; D011993:Recombinant Fusion Proteins; D011994:Recombinant Proteins; D012313:RNA; D005982:Glutathione Transferase; D047390:Casein Kinase II; D017346:Protein Serine-Threonine Kinases; C447612:CDK11a protein, human; D018844:Cyclin-Dependent Kinases; D012319:RNA Polymerase II