在乳腺癌细胞中,EPRS1的AKT依赖核定位激活了PARP1
Isaac Zin1,2, Arnab China1, Krishnendu Khan1
1Department of Cardiovascular and Metabolic Sciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44195.
概括
谷氨基烯基tRNA合成酶 (EPRS1) 移动到缺乏PTEN的乳腺癌细胞的核中,在那里它调节PARP1活动,影响DNA修复和瘤生长. 这表明针对EPRS1的目标.
科学领域:
- 分子生物学分子生物学
- 癌症生物学 癌症生物学
- 生物化学 生物化学
背景情况:
- 谷氨基烯酸-tRNA合成酶 (EPRS1) 对于蛋白质合成至关重要,也是多tRNA合成酶复合体 (MSC) 的一部分.
- 一些氨基酸-tRNA合成酶 (aaRSs) 在MSC之外执行非正规的功能.
- 失去PTEN在乳腺癌中很常见,并影响细胞信号通路.
研究的目的:
- 研究EPRS1在乳腺癌细胞中的作用和局部化.
- 确定PTEN/AKT信号与EPRS1核转移之间的关系.
- 阐明核EPRS1在调节DNA损伤反应和瘤进展方面的非正规功能.
主要方法:
- 免疫光显微镜评估EPRS1在乳腺癌细胞中的定位.
- PTEN抑制和AKT激活研究以诱导EPRS1核进口.
- 共同免疫沉以确定核 EPRS1 相互作用伙伴.
- siRNA对EPRS1和PARP1进行敲击,以评估功能后果.
- 对基因表达,DNA修复,细胞存活和瘤球体形成的分析.
主要成果:
- EPRS1存在于具有低PTEN表达的乳腺癌细胞的细胞核中,其核定位是由PTEN抑制或AKT激活诱导的.
- 核EPRS1与PARP1相互作用并调节其活性,减少蛋白质ADP-ribosylation.
- 抑制EPRS1或PARP1同样会损害DNA修复,减少癌细胞存活率,并抑制瘤球体的形成.
- EPRS1的核定位与侵入性导管癌中的AKT激活有关.
结论:
- EPRS1在核中表现出非正规的功能,调节PTEN缺陷乳腺癌中PARP1活性和DNA损伤反应.
- PTEN/AKT通路控制了EPRS1的核定位,将PTEN损失与PARP1激活和瘤生长联系起来.
- 针对EPRS1的非正规功能为乳腺癌提供了潜在的治疗策略,可能与PARP1抑制剂结合使用.
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