Mechanism of DNA damage responses mediated by acetylation of non-histone proteins

我们最近发现了一些参与DNA损伤反应的非组蛋白靶蛋白，它们在体外被组蛋白乙酰转移酶（如CBP和p300）乙酰化。在鉴定的乙酰化蛋白中，DNA双链断裂（DSB）诱导了人Rad52蛋白的乙酰化。我们用体外乙酰化纯化的Rad52蛋白，用质谱法鉴定了Rad52的乙酰化位点。辐射诱导的同源重组被乙酰化位点的突变所抑制。我们的研究结果表明，通过同源重组修复DSB需要Rad52的乙酰化。

We have newly identified several non-histone target proteins involved in DNA damage response, which are acetylated by histone acetyltransferases such as CBP and p300 in vitro. Among the identified acetylated proteins, acetylation of human Rad52 protein was induced after DNA double-strand break (DSB). We identified the acetylation sites of Rad52 by mass spectrometry with the in vitro- acetylated purified Rad52 protein. Radiation-induced homologous recombination was inhibited by mutations at the acetylated sites. Our results indicates that acetylation of Rad52 is required for DSB repair by homologous recombination.