非结构化的α-tubulin C-终端尾部的可访问性由微管网格形状控制
Takashi Hotta1, Morgan L Pimm1, Ezekiel C Thomas1
1Department of Cell & Developmental Biology, University of Michigan, Ann Arbor, MI, USA.
bioRxiv : the preprint server for biology
|October 3, 2025
概括
微管中的氨酸α-氨酸C端尾 (Y-αCTT) 是令人惊的难以接近的. 它的可访问性是由管蛋白构成调节的,受Taxol,微管相关蛋白 (MAPs) 和核酸状态等药物影响.
科学领域:
- 细胞生物学 细胞生物学
- 细胞骨的动力学
- 蛋白质结构 蛋白质结构
背景情况:
- 微管,对于细胞力学,迁移和分裂至关重要,从管中自组装.
- 虽然β-氨酸核酸状态得到了很好的研究,但α-氨酸和β-氨酸的C端尾 (CTT) 仍然不太了解.
- 假设CTT从微管表面自由突出.
研究的目的:
- 研究氨酸α-氨酸CTT (Y-αCTT) 的可访问性和调节.
- 探索影响微管网内的Y-αCTT可访问性的因素.
主要方法:
- 开发了三种针对Y-αCTT的新型生物传感器.
- 生物传感器与微管结合的实时成像.
- 素子单元相互作用的分子动力学模拟.
主要成果:
- 实时成像显示,在正常细胞条件下,Y-αCTT在很大程度上是无法访问的.
- Y-αCTT探针结合在Taxol治疗,特定MAPs的表达或非水解性GTP管的表达时增加.
- 分子动力学模拟显示了由氨酸核酸状态调节的短暂Y-αCTT相互作用.
结论:
- Y-αCTT的可访问性不是构成性的,而是动态调节的.
- 由核酸状态和MAPs影响的氨酸子单元的局部构造变化控制Y-αCTT暴露.
- 这一发现为超越核酸状态的微管调节提供了新的见解.
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