TY - JOUR
T1 - Lysines 3241 and 3260 of DNA-PKcs are important for genomic stability and radioresistance
AU - Mori, Eiichiro
AU - Davis, Anthony J.
AU - Hasegawa, Masatoshi
AU - Chen, David J.
N1 - Funding Information:
The work was supported by the National Institute of Health [ CA50519 and CA13499 to DJC] and the Cancer Prevention Research Institute of Texas [ RP110465 to DJC].
Publisher Copyright:
© 2016 Elsevier Inc.
PY - 2016/8/19
Y1 - 2016/8/19
N2 - DNA-dependent protein kinase (DNA-PK) is a serine/threonine kinase that plays an essential role in the repair of DNA double-strand breaks (DSBs) in the non-homologous end-joining (NHEJ) pathway. The DNA-PK holoenzyme consists of a catalytic subunit (DNA-PKcs) and DNA-binding subunit (Ku70/80, Ku). Ku is a molecular sensor for double-stranded DNA and once bound to DSB ends it recruits DNA-PKcs to the DSB site. Subsequently, DNA-PKcs is activated and heavily phosphorylated, with these phosphorylations modulating DNA-PKcs. Although phosphorylation of DNA-PKcs is well studied, other post-translational modifications of DNA-PKcs are not. In this study, we aimed to determine if acetylation of DNA-PKcs regulates DNA-PKcs-dependent DSB repair. We report that DNA-PKcs is acetylated in vivo and identified two putative acetylation sites, lysine residues 3241 and 3260. Mutating these sites to block potential acetylation results in increased radiosensitive, a slight decrease in DSB repair capacity as assessed by γH2AX resolution, and increased chromosomal aberrations, especially quadriradial chromosomes. Together, our results provide evidence that acetylation potentially regulates DNA-PKcs.
AB - DNA-dependent protein kinase (DNA-PK) is a serine/threonine kinase that plays an essential role in the repair of DNA double-strand breaks (DSBs) in the non-homologous end-joining (NHEJ) pathway. The DNA-PK holoenzyme consists of a catalytic subunit (DNA-PKcs) and DNA-binding subunit (Ku70/80, Ku). Ku is a molecular sensor for double-stranded DNA and once bound to DSB ends it recruits DNA-PKcs to the DSB site. Subsequently, DNA-PKcs is activated and heavily phosphorylated, with these phosphorylations modulating DNA-PKcs. Although phosphorylation of DNA-PKcs is well studied, other post-translational modifications of DNA-PKcs are not. In this study, we aimed to determine if acetylation of DNA-PKcs regulates DNA-PKcs-dependent DSB repair. We report that DNA-PKcs is acetylated in vivo and identified two putative acetylation sites, lysine residues 3241 and 3260. Mutating these sites to block potential acetylation results in increased radiosensitive, a slight decrease in DSB repair capacity as assessed by γH2AX resolution, and increased chromosomal aberrations, especially quadriradial chromosomes. Together, our results provide evidence that acetylation potentially regulates DNA-PKcs.
KW - Acetylation
KW - DNA double-strand breaks
KW - DNA-PKcs
KW - Non-homologous end-joining
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U2 - 10.1016/j.bbrc.2016.06.048
DO - 10.1016/j.bbrc.2016.06.048
M3 - Article
C2 - 27297111
AN - SCOPUS:84976618115
SN - 0006-291X
VL - 477
SP - 235
EP - 240
JO - Biochemical and Biophysical Research Communications
JF - Biochemical and Biophysical Research Communications
IS - 2
ER -