MLL/WDR5复合体招募中心卫星蛋白Cep72,以调节微管核和形形成
Swathi Chodisetty1,2, Aditi Arora1,3, Kausika Kumar Malik1
1Laboratory of Cell Cycle Regulation, Centre for DNA Fingerprinting and Diagnostics (CDFD), Hyderabad 500039, India.
Science advances
|December 11, 2024
概括
混合系白血病 (MLL) 蛋白质对于微管组织在中心体至关重要. 丧失MLL/WDR5影响细胞分裂和染色体对齐,揭示MLL在神经发育障碍中的新作用.
科学领域:
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
背景情况:
- 中心体功能障碍与小头症有关.
- 混合血统白血病 (MLL/KMT2A) 的哈普隆缺陷导致维德曼-施泰纳综合征 (WSS),这是一个带有小头症的神经发育障碍.
- 在中心体中MLL的确切功能尚不清楚.
研究的目的:
- 为了研究MLL/WDR5复合体在中心体中的作用.
- 确定MLL/WDR5如何影响微管组织和中心体功能.
- 阐明Cep72被MLL/WDR5.5招募到中心体的机制.
主要方法:
- 对缺乏MLL/WDR5.5的细胞中微管核和再生的分析.
- 免疫定位研究以确定MLL/WDR5,Cep72和γ-TuRCs的亚细胞定位.
- 在MLL/WDR5缺陷细胞中,在线粒分裂期间评估线圈形成和染色体对齐.
- 生物化学试验证实了MLL/WDR5和Cep72之间的相互作用.
主要成果:
- 丧失MLL/WDR5会影响微管细胞核和再生.
- MLL/WDR5定位在周心状物质上,并与Cep72和γ-TuRCs相互作用.
- MLL/WDR5促进γ-TuRCs和AKAP9的中心体局部化,这是WSS患者细胞中发现的表型.
- 缺少MLL,WDR5或Cep72会扰乱线的形成,并导致染色体错位.
- MLL和WDR5对于招募Cep72到中心体至关重要.
结论:
- 在中心体中,MLL具有以前未知的功能,调节微管组织.
- 该MLL/WDR5复合体对于适当的中心细胞功能和线粒细胞的进展至关重要.
- 通过MLL/WDR5介导的Cep72向中心体的招募是维持基因组稳定性和正常发育的关键机制.
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