p14ARF在与NPM1相隔时形成中等尺度组件
Eric Gibbs1, Qi Miao1, Mylene Ferrolino1
1Department of Structural Biology, St. Jude Children's Research Hospital, Memphis, Tennessee, USA.
Nature communications
|November 11, 2024
概括
核蛋白NPM1通过形成凝状网络来稳定瘤抑制剂p14ARF. 这种NPM1-p14ARF相互作用调节核细胞应激反应并减少细胞增殖,为癌症抑制机制提供了洞察力.
科学领域:
- 分子生物学分子生物学
- 细胞生物学 细胞生物学
- 生物化学 生物化学
背景情况:
- 核蛋白NPM1是一种参与核糖体生物发生,核糖体应激反应和瘤抑制的核细胞陪伴者.
- NPM1调节p14替代阅读框架 (p14ARF) 瘤抑制蛋白,抑制MDM2,稳定p53,并在致癌性压力下停止细胞循环.
- 在正常情况下,NPM1稳定核细胞中的p14ARF,防止p53的激活.
研究的目的:
- 阐明NPM1调节p14的结构机制.
- 了解NPM1介导的p14ARF调节如何影响细胞核功能和细胞过程.
主要方法:
- 对p14ARF-NPM1复合物的结构分析.
- 研究分子间接触和疏水相互作用在复杂形成中的作用.
- 评估NPM1-p14ARF组件对核分裂和细胞增殖的影响.
主要成果:
- 通过与NPM1.1相隔,ARF通过相隔形成一种凝状的中等尺度网络.
- 在p14ARF的部分折叠的N端区域内的分子间疏水接触介导了这种组合.
- 这种相位分离增强了p14ARF的核定位,限制了NPM1的扩散,并减少了细胞的增殖.
结论:
- NPM1通过促进p14ARF阶段分离和组装成一个中等尺度网络,充当一个陪伴者.
- 这种机制将p14ARF的部分折叠和核细胞定位与其调节细胞增殖和应激反应的功能联系在一起.
- 这些发现为NPM1在核细胞生物学和瘤抑制中的多方面的作用提供了结构性的见解.
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