TY - JOUR
T1 - DNA-dependent protein kinase (Ku protein-p350 complex) assembles on double-stranded DNA
AU - Suwa, Akira
AU - Hirakata, Michito
AU - Takeda, Yoshihiko
AU - Jesch, Stephen A.
AU - Mimori, Tsuneyo
AU - Hardin, John A.
PY - 1994/7/19
Y1 - 1994/7/19
N2 - The Ku protein is an autoantigen that consists of 70- and 80-kDa polypeptides. It associates with double-stranded DNA at free ends. In the present study, we examined the ability of anti-Ku antibodies to immunoprecipitate various structures from extracts of HeLa cells prepared at different salt concentrations. Under physiological conditions, these antibodies identified a complex containing the Ku protein and the 350-kDa component (p350) of DNA-dependent protein kinase (DNA-PK), which appeared to be closely associated on the DNA strand. In reconstitution experiments with cell extracts and biochemically purified components, the Ku protein-p350 complex formed only in the presence of double-stranded DNA. The reconstituted complex was catalytically active. Together with previous studies, these results indicate that the Ku protein interacts with DNA to create a binding site for p350 as the DNA-PK holoenzyme assembles.
AB - The Ku protein is an autoantigen that consists of 70- and 80-kDa polypeptides. It associates with double-stranded DNA at free ends. In the present study, we examined the ability of anti-Ku antibodies to immunoprecipitate various structures from extracts of HeLa cells prepared at different salt concentrations. Under physiological conditions, these antibodies identified a complex containing the Ku protein and the 350-kDa component (p350) of DNA-dependent protein kinase (DNA-PK), which appeared to be closely associated on the DNA strand. In reconstitution experiments with cell extracts and biochemically purified components, the Ku protein-p350 complex formed only in the presence of double-stranded DNA. The reconstituted complex was catalytically active. Together with previous studies, these results indicate that the Ku protein interacts with DNA to create a binding site for p350 as the DNA-PK holoenzyme assembles.
KW - human autoantigen Ku
KW - transcription factor
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U2 - 10.1073/pnas.91.15.6904
DO - 10.1073/pnas.91.15.6904
M3 - Article
C2 - 8041718
AN - SCOPUS:0028263785
SN - 0027-8424
VL - 91
SP - 6904
EP - 6908
JO - Proceedings of the National Academy of Sciences of the United States of America
JF - Proceedings of the National Academy of Sciences of the United States of America
IS - 15
ER -