相关实验视频
Updated: Jun 20, 2025

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Purification of Ubiquitinated p53 Proteins from Mammalian Cells
Published on: March 21, 2022
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在GRAIL1中,GRAIL1通过Ubiquitin Ligase独立的伴侣调节功能稳定了错误折叠的突变p53
Paramita Ray1, Sangeeta Jaiswal2, Daysha Ferrer-Torres2
1Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan.
Molecular cancer research : MCR
|July 17, 2024
概括
研究人员发现了一种降解突变p53的新方法,这是一种驱动食道癌的蛋白质. 一种新针对热冲击蛋白40/DNAJ,抑制其伴侣活性以减少癌细胞存活率.
科学领域:
- 分子生物学分子生物学
- 在瘤学瘤学.
- 生物化学 生物化学
背景情况:
- 在食道腺癌 (EAC) 中,TP53突变很常见,导致蛋白质稳定,预后不佳和治疗抵抗.
- 在巴雷特食道向EAC的进展过程中,E3泛素酶RNF128 (GRAIL) 异型1稳定突变p53.
- 在此之前,GRAIL稳定突变p53的机制是未知的.
研究的目的:
- 阐明GRAIL稳定突变p53.3的机制.
- 确定一种针对EAC突变p53稳定性的新型治疗策略.
主要方法:
- 进行了生物化学和细胞生物学研究.
- 研究了GRAIL和DNAJ之间的相互作用.
- 过度表达GRAIL片段 (Frag-J) 和一个细胞透性 (Pep-J) 用于抑制DNAJ-Hsp70辅助器的活性.
- 评估了对细胞存活和有机体生长的影响.
主要成果:
- GRAIL 具有一个 DNAJ 结合域 (315-PMCKCDILKA-325).
- 这种相互作用调节DNAJ伴侣活动,影响错误折叠的突变p53的稳定性.
- Frag-J和Pep-J降解了错误折叠的突变p53,降低了EAC和失塑的巴雷特食道细胞的存活率,并抑制了患者衍生的有机体生长.
- 佩普-J的效果与simvastatin相似.
结论:
- 在GRAIL中发现了一种新的,与ubiquitin-ligase无关的,伴侣调节域.
- 合成了一种第一类 (Pep-J),可以降解错误折叠的突变p53.
- 这种表明了治疗EAC和相关疾病的翻译潜力.
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