dSarm/Sarm1是激活受伤诱导的轴突死亡途径所需的
Jeannette M Osterloh1, Jing Yang, Timothy M Rooney
1Department of Neurobiology, University of Massachusetts Medical School, Worcester, MA 01605, USA.
Science (New York, N.Y.)
|June 9, 2012
概括
失去了无菌的α/Armadillo/Toll-Interleukin受体同质域蛋白 (Sarm1) 基因,可以防止轴突在受伤后自我破坏. 这一发现揭示了轴突死亡的古老,保存的途径,为神经损伤和神经退行性疾病提供了新的治疗点.
科学领域:
- 神经科学是一个神经科学.
- 细胞生物学 细胞生物学
- 遗传学 是一个遗传学.
背景情况:
- 轴突和突触退化是各种神经疾病的关键特征,包括外围神经病变,脑损伤和神经退行性疾病.
- 虽然轴突退化被认为涉及一个活跃的自我毁灭程序,但这种过程的强有力的基因阻断剂仍然难以捉摸.
研究的目的:
- 为了调查草毛虫收纳器适配器dSarm在轴突退化的作用.
- 确定 Sarm1 介导的信号是否在哺乳动物中保存,并有助于轴突死亡途径.
主要方法:
- 利用Drosophila dSarm的功能丧失突变来评估其对受伤后轴突退化的影响.
- 在体内和体外模型中检查了被切断的小鼠Sarm1无轴突的存活率.
主要成果:
- 在Drosophila细胞中dSarm的丧失 - - 自主抑制了在脱术后长时间的瓦勒里亚变性.
- 在小鼠中缺少Sarm1的切断轴突显示出显著的长期存活率,无论是体内还是体外.
- 这些发现表明,Sarm1信号在受伤后积极促进轴突破坏,并在物种中得到保护.
结论:
- 轴突在受伤后具有积极的自我破坏机制.
- 无菌的α/Armadillo/Toll-Interleukin受体同质域蛋白 (Sarm1) 是一个古老和保存的轴突死亡途径的关键组成部分.
- 向Sarm1为涉及轴突退化的疾病提供了潜在的治疗策略.
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