在抗体多样化过程中,Fam72a强制修复容易发生错误的DNA
Mélanie Rogier1,2,3,4, Jacques Moritz1,2,3,4, Isabelle Robert1,2,3,4
1Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Illkirch, France.
Nature
|November 25, 2021
概括
科学家发现FAM72A调节了免疫反应至关重要的DNA修复途径. 通过与 uracil DNA glycosylase (UNG2) 相互作用,FAM72A 控制 DNA 修复,影响 B 细胞受体多样化,并可能影响癌症的发展.
科学领域:
- 免疫学
- 分子生物学
- 遗传学
背景情况:
- 幽默性免疫反应取决于DNA损伤,突变和易发生错误的DNA修复.
- B细胞受体多样化涉及体质突变和类切换重组,由激活诱导的cytidine deaminase (AID) 启动.
- 在这些过程中,DNA修复途径产生突变和DNA断裂的确切机制尚未完全理解.
研究的目的:
- 确定参与类交换重组的新基因.
- 阐明FAM72A在DNA修复和B细胞多样化中的作用.
- 了解FAM72A调节对瘤发生的影响.
主要方法:
- 全基因组的CRISPR-Cas9淘汰屏幕用于类切换重组基因.
- 来自Fam72a淘汰小鼠的B细胞分析.
- 研究FAM72A-UNG2相互作用和乌拉切除的生物化学测试.
主要成果:
- FAM72A被确定为与 uracil DNA glycosylase 2 (UNG2) 相互作用的关键蛋白.
- 由于UNG2水平的变化,Fam72a淘汰B细胞的类交换重组和体质突变有缺陷.
- FAM72A调节了UNG2降解,影响了易出错和无错DNA修复之间的平衡.
结论:
- FAM72A控制了UNG2的生理水平,从而调节了乌拉切除和DNA修复途径.
- FAM72A-UNG2相互作用的失调可能会将DNA修复转向突变性过程,从而可能导致癌症.
- 这些发现为B细胞多样化的分子机制提供了洞察力,并对癌症研究产生了影响.
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