Hsp70的伴奏子,Ssa1和Ssa2,限制了多A) 结合蛋白质聚合
Hannah E Buchholz1, Sean A Martin1, Jane E Dorweiler1
1Department of Biological Sciences, Marquette University, Milwaukee, WI 53201-1881.
Molecular biology of the cell
|April 9, 2025
概括
在酵母中失去Hsp70伴侣会导致内源Pab1蛋白聚合. 过度表达其他伴侣素,如Hsp104和Sis1,可以防止这种情况发生,这表明Hsp70是如此.
科学领域:
- 细胞生物学 细胞生物学
- 蛋白质平衡是蛋白质的平衡.
- 分子陪伴者分子陪伴者
背景情况:
- Hsp70陪伴者对于蛋白质折叠和防止聚合至关重要.
- 缺乏Ssa1和Ssa2 Hsp70s的酵母表现出减少的生长和寿命.
- 缺乏Hsp70的细胞内源性蛋白质的行为尚不清楚.
研究的目的:
- 为了研究内源性野生型Poly A结合蛋白 (Pab1) 在有限Hsp70.0.的酵母中的聚合.
- 为了确定其他陪伴者是否可以补偿Hsp70缺乏.
- 了解Hsp70在与年龄相关的蛋白质聚合中的作用.
主要方法:
- 使用了缺乏Ssa1和Ssa2 Hsp70蛋白质的酵母菌株.
- 在正常和热冲击条件下观察到大型Pab1内涵的形成.
- 评估过度表达Ssa1,Hsp104和Sis1对Pab1聚合的影响.
- 在Pab1含有物存在时分析了应力颗粒动力学.
主要成果:
- 野生型Pab1在约一半的ssa1Δssa2Δ酵母细胞中形成大型细胞质内含体,而无应激.
- 过度表达Ssa1,Hsp104或Sis1显著减少了Pab1的入形成.
- 应力颗粒独立于Pab1内含物形成,但同时发生会减缓拆卸.
- 在和的野生型培养物中也形成Pab1内含物,并且可以通过Ssa1过度表达来部分挽救.
结论:
- 在健康细胞中,hsp70伴侣体限制了内源性蛋白质聚合.
- 活性Hsp70的耗尽可能导致与年龄相关的蛋白质聚合.
- 其他伴奏子,如Hsp104和Sis1,可以部分补偿Hsp70的损失.
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