Radiation-induced XRCC4 Association with Chromatin DNA Analyzed by Biochemical Fractionation
スポンサーリンク
概要
- 論文の詳細を見る
XRCC4, in association with DNA ligase IV, is thought to play a critical role in the ligation of two DNA ends in DNA double-strand break (DSB) repair through non-homologous end-joining (NHEJ) pathway. In the present study, we captured radiation-induced chromatin-recruitment of XRCC4 by biochemical fractionation using detergent Nonidet P-40. A subpopulation of XRCC4 changed into a form that is resistant to the extraction with 0.5% Nonidet P-40-containing buffer after irradiation. This form of XRCC4 was liberated by micrococcal nuclease treatment, indicating that it had been tethered to chromatin DNA. This chromatin-recruitment of XRCC4 could be seen immediately (< 0.1 hr) after irradiation and remained up to 4 hr after 20 Gy irradiation. It was seen even after irradiation of small doses, i.e., 2 Gy, but the residence of XRCC4 on chromatin was very transient after 2 Gy irradiation, returning to near normal level in 0.2–0.5 hr after irradiation. The chromatin-bound XRCC4 represented only ~1% of total XRCC4 molecules even after 20 Gy irradiation and the quantitative analysis using purified protein as the reference suggested that only a few XRCC4-DNA ligase IV complexes were recruited to each DNA end. We further show that the chromatin-recruitment of XRCC4 was not attenuated by wortmannin, an inhibitor of DNA-PK, or siRNA-mediated knockdown of the DNA-PK catalytic subunit (DNA-PKcs), indicating that this process does not require DNA-PKcs. These results would provide us with useful experimental tools and important insights to understand the DNA repair process through NHEJ pathway.
論文 | ランダム
- 縫合のテクニック (特集 実地医家のための図解小外科テクニック)
- 513 衝突時の立位の乗客の運動挙動シミュレーション(S10-3 衝突安全と生体工学(2),S10 衝突安全と生体工学)
- 4002 衝突時の人体に及ぼすシート剛性の影響シミュレーション(J19 交通機械のダイナミクス,2005年度年次大会)
- 615 二輪樹脂部品における成形解析活用と効果(一般:加工技術,システム技術,学術講演)
- オ-ジェ電子分析法(AESUによる鉄鋼の表面分析の定量法)