XBP1拼接有助于内细胞网膜压力诱导的人类小岛粉样蛋白多上调节
Yun Zhang1, Susan Lin2, Jing Yao1
1National Clinical Research Center for Geriatric Disorders, Xuanwu Hospital, Capital Medical University, Beijing 100053, China.
Genes & diseases
|July 12, 2024
概括
细胞内膜网膜 (ER) 的压力通过激活X盒结合蛋白1 (XBP1) 拼接,提高了人类β细胞中小岛氨基多 (IAPP) 的表达. 阻止这种途径可以改善β细胞的功能和存活率,从而提供对2型糖尿病的见解.
科学领域:
- 分子生物学分子生物学
- 内分泌学 在内分泌学.
- 细胞生物学 细胞生物学
背景情况:
- 由岛屿粉样蛋白聚 (IAPP) 聚合形成的岛屿粉样蛋白是2型糖尿病 (T2DM) 的标志.
- 细胞内膜网膜 (ER) 压力与T2DM病原发生有关,并与IAPP聚合物相互作用.
研究的目的:
- 调查ER应激在T2DM病原发生中的作用.
- 为了阐明人类β细胞中ER压力对人类IAPP (hIAPP) 的转录调节.
主要方法:
- 在人类β细胞中克隆和分析hIAPP促进体活性.
- 位点定向的突变发生来破坏潜在的X盒结合蛋白1 (XBP1) 结合位点.
- 使用XBP1拼接抑制剂 (MKC3946) 的治疗.
主要成果:
- 在人体β细胞中,ER压力显著增强了hIAPP促进因子的活性和表达.
- 确定XBP1拼接是调解ER压力诱导hIAPP上调调节的机制.
- 破坏XBP1结合部位消除了ER应激对hIAPP促进体活性的影响.
- 通过MKC3946抑制XBP1拼接,降低了ER压力诱导的hIAPP上调和改善了β细胞生存和功能.
结论:
- ER压力通过XBP1.1直接影响hIAPP在转录水平的表达.
- 这种机制有助于IAPP细胞毒性和T2DM的发病.
- 针对ER压力-XBP1-IAPP通路可能为T2DM提供新的治疗策略.
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