Stimulation of the DNA-dependent protein kinase by RNA polymerase II transcriptional activator proteins.
The DNA-dependent protein kinase (DNA-PK) phosphorylates RNA polymerase II and a number of transcription factors. We now show that the activity of DNA-PK is directly stimulated by certain transcriptional activator proteins, including the human heat shock transcription factor 1 (HSF1) and a transcriptionally active N-terminal 147 amino acid GAL4 derivative. Stimulation of DNA-PK activity required specific sequences in the activator proteins outside the minimal DNA binding domains. The stimulation of DNA-PK activity also required DNA and was greater with DNA containing relevant activator binding sites. Comparison of different HSF binding fragments showed that optimal stimulation occurred when two HSF binding sites were present. Stimulation with HSF and GAL4 was synergistic with Ku protein, another regulator of DNA-PK activity. DNA-PK is tightly associated with the transcriptional template, and an increase in its activity could potentially influence transcription through the phosphorylation of proteins associated with the transcription complex.
Peterson
S R
SR
Department of Chemistry and Biochemistry, University of Colorado, Boulder 80309-0215.
Jesch
S A
SA
Chamberlin
T N
TN
Dvir
A
A
Rabindran
S K
SK
Wu
C
C
Dynan
W S
WS
D034961:Antigens, Nuclear; D004265:DNA Helicases; D051747:DNA-Activated Protein Kinase; D004268:DNA-Binding Proteins / Q000378:metabolism; D004789:Enzyme Activation; D006367:HeLa Cells; D000076249:Heat Shock Transcription Factors; D006801:Humans; D000072200:Ku Autoantigen; D009687:Nuclear Proteins / Q000378:metabolism; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism*; D012319:RNA Polymerase II / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins; D013379:Substrate Specificity; D015534:Trans-Activators / Q000378:metabolism*; D014157:Transcription Factors / Q000378:metabolism
D034961:Antigens, Nuclear; D004268:DNA-Binding Proteins; C064255:GAL4 (1-147) protein, S cerevisiae; C000619706:HSF1 protein, human; D000076249:Heat Shock Transcription Factors; D009687:Nuclear Proteins; D029701:Saccharomyces cerevisiae Proteins; D015534:Trans-Activators; D014157:Transcription Factors; D051747:DNA-Activated Protein Kinase; C497263:PRKDC protein, human; D017346:Protein Serine-Threonine Kinases; D012319:RNA Polymerase II; D004265:DNA Helicases; C106893:XRCC5 protein, human; C000606509:Xrcc6 protein, human; D000072200:Ku Autoantigen