TMEM106B C端片段聚合并驱动神经退行性蛋白质病变
Ruben Riordan1,2, Aleen Saxton1, Pamela J McMillan1,3
1Geriatrics Research Education and Clinical Center, Veterans Affairs Puget Sound Health Care System, Seattle, WA 98108, USA.
bioRxiv : the preprint server for biology
|June 25, 2024
概括
跨膜蛋白106B (TMEM106B) 在C. elegans模型中,C端片段聚合导致神经退行. 这种聚合驱动神经元功能障碍和损失,独立于益格拉努林水平,为蛋白质病变提供了洞察力.
科学领域:
- 神经科学是一个神经科学.
- 遗传学 是一个遗传学.
- 分子生物学分子生物学
背景情况:
- 跨膜蛋白106B (TMEM106B) 的遗传变异与神经退行性疾病有关,特别是前叶退行 (FTLD).
- 低温电子显微镜揭示了FTLD,阿尔茨海默氏症,PSP和DLB大脑中的TMEM106BC终端 (TMEM CT) 聚合物,这表明在多蛋白质病变中发挥了作用.
- TMEMCT聚合的精确分子机制和神经退行潜力尚不清楚.
研究的目的:
- 描述TMEM106B C端片段的聚合倾向和神经退行潜力.
- 建立一个新的转基因C. elegans模型来研究TMEM106B蛋白质病变.
- 为了研究前列腺素 (PGRN) 和病途径在TMEM106B聚合中的作用.
主要方法:
- 生成的转基因C. elegans表达神经元中的人类TMEM CT片段.
- 进行行为分析以评估神经元功能障碍.
- 研究了PGRN损失 (pgrn-1淘汰赛) 和病抑制基因 (spop-1, sut-2, sut-6淘汰赛) 对TMEMCT病理学的影响.
主要成果:
- 在C. elegans中,TMEM CT的泛神经表达诱导了神经功能障碍和GABAergic神经元损失.
- 细胞质TMEMCT聚合与行为缺陷和神经退行相关.
- 失去pgrn-1并没有影响TMEM CT模型的运动表型,这表明聚合发生在PGRN的下游.
- 淘汰病抑制剂显示出最小的救援,表明TMEM106B蛋白质病变的独特机制.
结论:
- TMEMCT聚合足以引起神经退行.
- C. elegans TMEM CT模型是研究TMEM106B蛋白质病变的宝贵工具.
- TMEM106B蛋白质病变机制似乎与PGRN缺乏和病变不同.
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