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在染色体末端连接过程中,PAXX和MRI的功能不同

Metztli Cisneros-Aguirre^1,2, Felicia Wednesday Lopezcolorado¹, Xiaoli Ping³

¹Department of Cancer Genetics and Epigenetics, Beckman Research Institute of the City of Hope, 1500 E Duarte Rd., Duarte, CA 91010 USA.

bioRxiv : the preprint server for biology

|September 4, 2024

概括

PAXX和MRI是通过单独的Canonical Nonhomologous End Joining (C-NHEJ) 进行DNA修复的必要条件. 然而,当DNA-PKcs被抑制时,PAXX对于粗的DNA双链断裂 (DSB) 修复至关重要,而当XLF被破坏时,MRI至关重要.

科学领域:

分子生物学分子生物学
遗传学遗传学是一个
DNA 修复机制的修复机制

背景情况:

规范性非同类末端连接 (C-NHEJ) 是一种主要的DNA双链断裂 (DSB) 修复途径.
DSB末端的突触是一个关键的步骤,由DNA-PKcs,XLF和潜在的PAXX等蛋白质介导.
PAXX和MRI是Ku-结合因子,其在C-NHEJ中的作用需要进一步阐明.

研究的目的:

研究PAXX在染色体DSB的C-NHEJ中的作用.
为了比较PAXX的功能与另一种Ku-结合因子,MRI.
了解PAXX,MRI,DNA-PKcs和XLF在DSB修复中的相互作用.

主要方法:

使用Cas9报告员来评估的DSB的末端连接 (EJ),作为C-NHEJ的读数.
研究了PAXX和MRI干扰的影响,单独和与DNA-PKcs或XLF干扰/抑制相结合.
分析了不同类型的突变,包括大删除和微同学介导的删除.

主要成果:

单独作用时,对于C-NHEJ的形DSBs来说,PAXX和MRI是不可用的.
在DNA-PKcs中断时,PAXX对于粗的DSB EJ变得至关重要,特别是在激酶抑制时.
当XLF被破坏时,MRI对于的DSB EJ很重要,PAXX也观察到这样的作用.
失去了XLF会导致大缺失的增加,而MRI损失会加剧,与DNA-PKcs抑制不同.

结论:

PAXX促进了C-NHEJ中的DSB末端突触,显示了DNA-PKcs和XLF的部分冗余.
磁力共振成像在C-NHEJ中起着重要作用,主要是在XLF功能受损时.
这项研究突出了PAXX和MRI在DNA双链断裂修复途径中的复杂,上下文依赖的作用.

关键词:

生物科学生物科学这就是C-NHEJJ.这就是DNA-PKcscs.遗传学遗传学是一个这就是为什么MRI是MRI.PAXXXX PAXXXX PAXXXX PAXXXX PAXXXX PAXXXX PAXXXX PAXXXX PAXXXX PAXXXX PAXXXX PAXXXX PAXXXX PAXXXX PAXXXX 一个XLF,一个XLF.染色体双链断裂的修复

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