Lysosomal 蛋白酶介导的 APP 降解是依赖pH的,对突变敏感的,并促进tau蛋白解
Caroline Ackley1, Zoe Liau1,2, Shruti Arya1
1Memory and Aging Center, Department of Neurology, University of California San Francisco, San Francisco, 100190, California, USA.
Research square
|July 17, 2025
概括
这项研究揭示了溶解体如何降解粉样蛋白前体蛋白 (APP) 和其碎片,为阿尔茨海默病 (AD) 和潜在的治疗点提供了新的见解.
科学领域:
- 神经科学是一个神经科学.
- 分子生物学分子生物学
- 生物化学 生物化学
背景情况:
- 阿尔茨海默病 (AD) 的特点是粉样蛋白β (Aβ) 积累,这种积累来自粉样蛋白前体蛋白 (APP).
- 虽然已知通过分泌酶处理APP,但其溶解体降解仍然不清楚.
- 在APP的突变可以导致早期发病的AD.
研究的目的:
- 为绘制由 lysosomal 蛋白酶 (cathepsins) 准的 APP 分裂部位的地图.
- 为了研究野生类型和突变型APP由cathepsins的降解.
- 探索APP在神经退行性疾病发病过程中的作用.
主要方法:
- 通过质谱法 (MSP-MS) 进行多重复合基质分析,以绘制APP裂变点的地图.
- 基于细胞的和体外的测试,以研究由甲素降解APP.
- 在存在病原体变异和pH值变化的情况下分析APP加工.
主要成果:
- APP存在于内解体区,并由多个cathepsins进行处理.
- APP分裂部位对pH和病原性APP变体 (E693G,E693Q) 很敏感.
- 在体外,APP (sAPP) 的可溶性域增强了 cathepsin G 的 tau 裂变.
结论:
- 在阿尔茨海默氏病的发病过程中,APP的溶酶体处理至关重要.
- 确定了APP和tau裂变之间的联系.
- 这些发现表明了针对阿尔茨海默病的溶酶体功能的新型治疗策略.
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