IGFBP6通过激活ATF4位和减少ER逆转移位子表达来调节蛋白质稳定
O E Kolodeeva1, O E Kolodeeva1, I D Antipenko1
1Faculty of Biology and Biotechnology, National Research University Higher School of Economics, Moscow, Russia.
Doklady. Biochemistry and biophysics
|October 31, 2024
概括
乳腺癌细胞中IGFBP6蛋白减少会增加转移. 这会影响蛋白质合成调节和细胞应激反应,影响蛋白质稳定和与ER相关的降解途径.
科学领域:
- 分子生物学分子生物学
- 癌症研究 癌症研究
- 细胞生物学 细胞生物学
背景情况:
- 减少胰岛素类生长因子结合蛋白6 (IGFBP6) 表达与增加乳腺癌 (BC) 转移潜力相关.
- 瘤细胞表现出较高的蛋白质合成,需要进行补偿性蛋白质稳定调整.
- 核糖体失活蛋白 (RIPs) 和素一样,是通过向核糖体来研究蛋白质稳定性的工具.
研究的目的:
- 调查IGFBP6基因淘汰对MDA-MB-231乳腺癌细胞系中蛋白质稳定性的影响.
- 阐明IGFBP6影响BC蛋白质合成和细胞应激反应的机制.
主要方法:
- 在MDA-MB-231 BC细胞系中利用IGFBP6基因淘汰.
- 通过素毒素评估核糖体修饰效率.
- 分析了参与ER相关降解 (ERAD) 和展开蛋白质反应 (UPR) 途径的关键蛋白质的表达水平.
主要成果:
- 被IGFBP6淘汰的MDA-MB-231细胞显示了由素减少的核糖体修饰.
- 这种减少的修饰可能与素催化子单元从ER到细胞质的运输受损有关.
- 观察到HRD1/Derlin亚单元 (ERAD成分) 的表达减少和ATF4向基因 (UPR通路) 的表达增加.
结论:
- 乳腺癌细胞中的IGFBP6缺乏会改变蛋白质稳定和细胞应激反应.
- 这些变化包括核糖体功能受损,ERAD效率降低以及UPR通路的激活.
- 了解这些机制可能为乳腺癌转移提供新的治疗点.
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