对ER压力诱导因子CRELD2的分子表征2
Shohei Hinaga1, Mahmoud Kandeel2,3, Kentaro Oh-Hashi4,5,6,7
1Graduate School of Natural Science and Technology, Gifu University, 1-1 Yanagido, Gifu, 501-1193, Japan.
Cell biochemistry and biophysics
|May 16, 2024
概括
这项研究表明,CRELD2表达受ATF6和ATF4转录因子的控制,在内细胞网膜应激过程中影响蛋白质稳态. 这些发现突出了CRELD2的发现.
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:
- 细胞内膜网膜 (ER) 应激反应对于维持细胞蛋白质平衡至关重要.
- CRELD2 (含氨酸丰富的环状域2) 是一种ER压力诱导蛋白.
- 对于CRELD2表达的调节机制及其在ER相关降解 (ERAD) 中的作用尚不完全了解.
研究的目的:
- 阐明转录因子ATF6和ATF4在调节ER压力下的CRELD2表达中的作用.
- 为了研究CRELD2与ERAD基质的相互作用.
- 了解CRELD2在ER压力期间对蛋白质稳态的贡献.
主要方法:
- 产生ATF6缺乏和ATF4缺乏的细胞系.
- 使用定量PCR和西式斑点分析CRELD2mRNA和蛋白质表达的分析.
- 路西法雷斯记者测量以评估主办方的活动.
- 同免疫沉试验用于研究蛋白质与蛋白质相互作用.
- 在CRELD2构造物的位点定向突变发生.
主要成果:
- 在转录层面上,ATF6缺乏抑制了尼卡米辛诱导的CRELD2表达.
- 缺少ATF4会降低CRELD2mRNA和蛋白质水平,也会降低ATF6的表达.
- GADD34抑制影响了CRELD2蛋白水平,但没有影响ATF6水平.
- 在CRELD2的CXXC基因中发生突变时,CRELD2与ERAD基质NHK相互作用,这表明该基因在蛋白质结合中发挥了作用.
- 这种相互作用独立于二硫化物键.
结论:
- 通过转录和后转录机制,CRELD2表达受到ATF6和ATF4的调节.
- CRELD2的N端CXC基因因涉及其与NHK等标蛋白的关联.
- 进一步描述CRELD2相互作用因子对于理解ER压力下的蛋白质稳态至关重要.
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