在肌缩侧面硬化症 (ALS) 中TDP-43的病理形式促进异常的端粒延长
Anna Konopka1, Md Shafi Jamali2, Megan Fowler1
1College of Medicine and Public Health, Flinders University, Australia.
概括
肌缩侧面硬化症 (ALS) 涉及由于TDP-43蛋白错位而导致的运动神经元损伤. 这项研究发现端粒保护受损,导致ALS模型中受TDP-43病理影响的神经元中的端粒变长.
科学领域:
- 神经科学是一个神经科学.
- 遗传学 遗传学 是一个
- 分子生物学分子生物学
背景情况:
- 肌缩侧面硬化症 (ALS) 的特征是运动神经元退化.
- 从细胞核到细胞质的TARDNA结合蛋白43 (TDP-43) 的错位是ALS的一个关键病理标志.
- 端粒,染色体末端的保护帽,以及与之相关的蛋白质,如TRF2,都与神经退行性疾病有关,此前关于ALS中端粒失调的研究结果是矛盾的.
研究的目的:
- 在TDP-43相关ALS (TDP-43rNLS) 的小鼠模型和表达TDP-43ALS突变的初级神经元中研究皮层神经元中的端粒失调.
- 在TDP-43病理的背景下,研究端粒重复结合因子2 (TRF2) 和端粒长度调节的作用.
主要方法:
- 对TDP-43 rNLS小鼠皮层神经元的端粒长度和变异性的分析与对照对照.
- 在TDP-43 rNLS小鼠中评估不同疾病阶段的TRF2表达水平.
- 检查表达TDP-43ALS突变 (A315T,A90V) 的原发皮质神经元中的端粒长度和TRF2表达.
- 在人类ALS脊髓溶解物中分析与端粒相关的基因 (TERT,Rif1) 和TRF2.
主要成果:
- 与对照小鼠相比,TDP-43 rNLS小鼠的端粒显著更长,变化更大.
- 在TDP-43 rNLS小鼠中,TRF2表达显示出最初的下调,然后是上调.
- 表达突变TDP-43的主要神经元表现出更长的端粒.
- 在人类ALS脊髓样本中观察到TRF2上调的趋势.
- 在小鼠模型和人类ALS样本中检测到TERT的失调和Rif1上调的趋势.
- 观察到的端粒延长独立于ALT机制,与DNA损伤无关.
结论:
- 在ALS中TDP-43病理与神经元中受损的端粒保护机制有关.
- 端粒失调,特别是延长,是TDP-43相关的ALS的一个特征.
- 这些发现表明,在ALS病变发生过程中涉及端粒生物学的新途径.
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