Permeant fluorescent probes visualize the activation of SARM1 and uncover an anti-neurodegenerative drug candidate.
Permeant fluorescent probes visualize the activation of SARM1 and uncover an anti-neurodegenerative drug candidate.
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DOI：
10.7554/elife.67381
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发表时间：
2021-05-04
期刊：
影响因子：
7.7
通讯作者：
Zhao YJ
中科院分区：
文献类型：
--
作者：
Li WH;Huang K;Cai Y;Wang QW;Zhu WJ;Hou YN;Wang S;Cao S;Zhao ZY;Xie XJ;Du Y;Lee CS;Lee HC;Zhang H;Zhao YJ
SARM1通过其nad代谢活性调节轴突变性，是神经退行性疾病的药物靶点。我们设计并合成了苯乙烯衍生物与吡啶的荧光共轭物作为SARM1的底物，该底物在转化后表现出较大的红移。使用这些偶联物，在内源性NMN升高或细胞浸润的NMN类似物处理后，活细胞中可以看到SARM1的激活。在神经元中，成像记录小鼠SARM1激活比长春新碱诱导的轴突变性早几个小时。文库筛选发现，尼索地平衍生物（NSDP）是SARM1的共价抑制剂，可与半胱氨酸反应，特别是与Cys311的ARM结构域反应，阻断其nmn活化，保护轴突免受退化。Cryo-EM结构显示，SARM1被抑制剂锁定为非活性构象，揭示了二氢吡啶的潜在神经保护机制。
SARM1 regulates axonal degeneration through its NAD-metabolizing activity and is a drug target for neurodegenerative disorders. We designed and synthesized fluorescent conjugates of styryl derivative with pyridine to serve as substrates of SARM1, which exhibited large red shifts after conversion. With the conjugates, SARM1 activation was visualized in live cells following elevation of endogenous NMN or treatment with a cell-permeant NMN-analog. In neurons, imaging documented mouse SARM1 activation preceded vincristine-induced axonal degeneration by hours. Library screening identified a derivative of nisoldipine (NSDP) as a covalent inhibitor of SARM1 that reacted with the cysteines, especially Cys311 in its ARM domain and blocked its NMN-activation, protecting axons from degeneration. The Cryo-EM structure showed that SARM1 was locked into an inactive conformation by the inhibitor, uncovering a potential neuroprotective mechanism of dihydropyridines.