The budding yeast Rad9 checkpoint protein is subjected to Mec1/Tel1-dependent hyperphosphorylation and interacts with Rad53 after DNA damage
The budding yeast Rad9 checkpoint protein is subjected to Mec1/Tel1-dependent hyperphosphorylation and interacts with Rad53 after DNA damage
复制标题
DOI：
10.1093/emboj/17.19.5679
复制
发表时间：
1998-10-01
期刊：
影响因子：
11.4
通讯作者：
Lowndes, NF
中科院分区：
文献类型：
--
作者：
Vialard, JE;Gilbert, CS;Lowndes, NF
酿酒酵母RAD9检查点基因是细胞周期短暂停滞和DNA修复基因转录诱导所必需的，针对RAD9蛋白的多克隆抗体在异步化培养中识别多种多肽，在S或G(2)/M期细胞中识别多肽，而在G(1)期细胞中观察到单一形式的多肽。用不同的DNA损伤剂，如紫外线、电离辐射或甲基甲烷磺酸盐处理后，蛋白质会出现高度修饰的形式。在正常细胞周期和DNA损伤后检测到的所有修饰对磷酸酶处理都很敏感，这表明它们是由磷酸化、损伤诱导的Rad9过度磷酸化导致的，与检查点功能(细胞周期停滞和转录诱导)相关，并且与细胞周期阶段和进展无关。在非同步培养中，Rad9的过度磷酸化依赖于ATE和ATM基因的同源基因Mec1和TEL1。在G1期细胞中，损伤依赖的过度磷酸化除了RAD17、RAD24、MEC3和DDC1外，还需要功能性的Mec1，这表明了检查点基因在这种对DNA损伤的反应中具有细胞周期阶段的特异性。DNA损伤后对检查点蛋白相互作用的分析表明，Rad9与Rad53存在物理联系。
The Saccharomyces cerevisiae RAD9 checkpoint gene is required for transient cell-cycle arrests and transcriptional induction of DNA repair genes in response to DNA damage, Polyclonal antibodies raised against the Rad9 protein recognized several polypeptides in asynchronous cultures, and in cells arrested in S or G(2)/M phases while a single form was observed in G(1)-arrested cells. Treatment with various DNA damaging agents, i,e, UV, ionizing radiation or methyl methane sulfonate, resulted in the appearance of hypermodified forms of the protein. All modifications detected during a normal cell cycle and after DNA damage were sensitive to phosphatase treatment, indicating that they resulted from phosphorylation, Damage-induced hyperphosphorylation of Rad9 correlated with check-point functions (cell-cycle arrest and transcriptional induction) and was cell-cycle stage- and progression-independent. In asynchronous cultures, Rad9 hyperphosphorylation was dependent on MEC1 and TEL1, homologues of the ATE and ATM genes. In G1-arrested cells, damage-dependent hyperphosphorylation required functional MEC1 in addition to RAD17, RAD24, MEC3 and DDC1, demonstrating cell-cycle stage specificity of the checkpoint genes in this response to DNA damage. Analysis of checkpoint protein interactions after DNA damage revealed that Rad9 physically associates with Rad53.