相关实验视频
Updated: May 29, 2025

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Purification of Hsp104, a Protein Disaggregase
Published on: September 30, 2011
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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 USA.
bioRxiv : the preprint server for biology
|February 3, 2025
概括
酵母中Hsp70蛋白质的损失导致内源Pab1蛋白质的聚合. 过度表达其他陪伴物或Hsp70可以防止这种情况,这表明Hsp70是Hsp70.
科学领域:
- 分子生物学分子生物学
- 细胞平衡是细胞的平衡.
- 蛋白质聚合蛋白质的聚合.
背景情况:
- 分子伴侣,特别是Hsp70蛋白 (酵母中的Ssa1和Ssa2),对于蛋白质折叠和防止聚合至关重要.
- 酵母中Ssa1和Ssa2的损失导致生长和寿命的减少,已知由错误折叠的蛋白质形成的包裹.
- 在有限的Hsp70条件下,内源性野生型蛋白质的行为仍然不清楚.
研究的目的:
- 在缺乏Ssa1和Ssa2.2的酵母中研究内源性野生类型Poly A结合蛋白 (Pab1) 的聚合.
- 确定Hsp70和其他伴侣在防止Pab1聚合中的作用.
- 了解Pab1含和应力颗粒对热冲击后细胞恢复的影响.
主要方法:
- 使用了野生类型的酵母菌株,其缺失在Ssa1和Ssa2 (ssa1Δssa2Δ).
- 使用Pab1-GFP光显微镜观察到Pab1的聚合.
- 评估过度表达Ssa1,Hsp104和Sis1对Pab1含量的影响.
- 在热冲击后监控应力颗粒形成和拆卸动力学.
主要成果:
- 在 ssa1Δssa2Δ 细胞中,野生型 Pab1 在大约一半的细胞中形成了大型细胞质内含,即使没有应激.
- 过度表达Ssa1,Hsp104或Sis1显著减少了Pab1的包容形成.
- 在野生型和 ssa1Δssa2Δ 细胞中的热冲击诱导应力颗粒 (SGs),无论Pab1的含量如何.
- 单独含有SG的细胞比野生类型更快地分解;含有Pab1的细胞和SG的细胞分解速度更慢.
- 在老野生类型酵母培养物中也观察到Pab1的含有,并且可以通过Ssa1过度表达来部分挽救.
结论:
- Hsp70陪伴剂限制了无压力和老化的酵母细胞中Pab1等内源蛋白质的聚合.
- 高水平的Ssa1,Hsp104或Sis1可以补偿降低的Hsp70水平,防止聚合.
- 在Pab1含和压力颗粒之间的相互作用影响细胞恢复动态.
- 活性Hsp70的耗尽可能导致与年龄相关的蛋白质聚合.
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