P53C-terminal phosphorylation by CHM and CHK2 participates in the regulation of DNA-Damage-induced C-terminal acetylation
P53C-terminal phosphorylation by CHM and CHK2 participates in the regulation of DNA-Damage-induced C-terminal acetylation
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DOI：
10.1091/mbc.e04-08-0689
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发表时间：
2005-04-01
影响因子：
3.3
通讯作者：
Shieh, SY
中科院分区：
文献类型：
--
作者：
Ou, YH;Chung, PH;Shieh, SY
肿瘤抑制蛋白 p53 介导应激诱导的生长停滞或细胞凋亡，并在维护基因组完整性方面发挥重要作用。为了响应 DNA 损伤，p53 可以通过磷酸化和乙酰化在多个位点进行修饰。我们报告了 CHK1 和 CHK2（两种丝氨酸/苏氨酸 (Ser/Thr) 蛋白激酶）对 p53 C 末端磷酸化的表征，之前与 p53 N 末端的磷酸化有关。使用胰蛋白酶磷酸肽图谱，我们鉴定了位于 p53 最后 100 个氨基酸中的另外 6 个 CHK1 和 CHK2 位点。 DNA 损伤会诱导其中至少三个位点（Ser366、Ser378 和 Thr387）的磷酸化，而针对 chk1 和 chk2 的小干扰 RNA 会消除 Ser366 和 Thr387 的诱导作用。此外，这些磷酸化位点的突变对 p53 C 末端乙酰化和 p53 靶向启动子的激活具有不同的影响。我们的结果证明了 p53 C 端磷酸化和乙酰化之间可能存在相互作用，并且它们提供了 CHK1 和 CHK2 控制 p53 活性的额外机制。
The tumor suppressor protein p53 mediates stress-induced growth arrest or apoptosis and plays a major role in safeguarding genome integrity. In response to DNA damage, p53 can be modified at multiple sites by phosphorylation and acetylation. We report on the characterization of p53 C-terminal phosphorylation by CHK1 and CHK2, two serine/threonine (Ser/Thr) protein kinases, previously implicated in the phosphorylation of the p53 N terminus. Using tryptic phosphopeptide mapping, we have identified six additional CHK1 and CHK2 sites residing in the final 100 amino acids of p53. Phosphorylation of at least three of these sites, Ser366, Ser378, and Thr387, was induced by DNA damage, and the induction at Ser366 and Thr387 was abrogated by small interfering RNA targeting chk1 and chk2. Furthermore, mutation of these phosphorylation sites has a different impact on p53 C-terminal acetylation and on the activation of p53-targeted promoters. Our results demonstrate a possible interplay between p53 C-terminal phosphorylation and acetylation, and they provide an additional mechanism for the control of the activity of p53 by CHK1 and CHK2.