Stimulation of DNA-dependent protein kinase activity by high mobility group proteins 1 and 2.
After incubation of high mobility group (HMG) proteins 1 and 2 with DNA-dependent protein kinase (DNA-PK) and [gamma-32P]ATP in the presence of double-stranded DNA, not only phosphorylation of HMG proteins but also enhancement of autophosphorylation of the catalytic polypeptide of 350 kDa in DNA-PK was observed. DNA-PK activity determined with a synthetic peptide and alpha-casein as substrates was stimulated several-fold by HMG1, HMG2, and the DNA-binding domains. The stimulation was decreased at higher concentrations of HMG proteins, and DNA-PK activity was inhibited by histone H1. Electrophoretic mobility shift analysis suggests that HMG proteins facilitate the binding of DNA-PK to DNA.
Watanabe
F
F
Medical Research Institute, Tokyo Medical and Dental University, Japan.
Shirakawa
H
H
Yoshida
M
M
Tsukada
K
K
Teraoka
H
H
D000255:Adenosine Triphosphate / Q000378:metabolism; D000595:Amino Acid Sequence; D001665:Binding Sites; D002364:Caseins / Q000378:metabolism; D002384:Catalysis; D004247:DNA / Q000494:pharmacology*; D004789:Enzyme Activation / Q000187:drug effects; D006609:High Mobility Group Proteins / Q000378:metabolism / Q000494:pharmacology*; D006657:Histones / Q000494:pharmacology; D008969:Molecular Sequence Data; D010766:Phosphorylation; D047428:Protein Kinase Inhibitors; D011494:Protein Kinases / Q000378:metabolism*; D013379:Substrate Specificity; D014407:Tumor Cells, Cultured
D002364:Caseins; D006609:High Mobility Group Proteins; D006657:Histones; D047428:Protein Kinase Inhibitors; D000255:Adenosine Triphosphate; D004247:DNA; D011494:Protein Kinases