The interaction between cytoplasmic dynein and dynactin is required for fast axonal transport
The interaction between cytoplasmic dynein and dynactin is required for fast axonal transport
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DOI：
10.1073/pnas.94.22.12180
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发表时间：
1997-10-28
影响因子：
11.1
通讯作者：
Holzbaur, ELF
中科院分区：
文献类型：
--
作者：
WatermanStorer, CM;Karki, SB;Holzbaur, ELF
快速轴突运输以膜细胞器的双向微管运动为特征。胞质动力蛋白是从突触到细胞体的逆行运输所必需的，但不是充分的，动力蛋白是一种异聚蛋白复合物，在神经元中富集，与微管和细胞质动力蛋白结合。为了确定动力蛋白是否为逆行轴突运输所必需，我们检测了抗动力蛋白抗体对挤压轴质中细胞器运输的影响。用dynactin的p150（glue）亚基抗体处理轴质导致基于微管的细胞器运输速度显著降低，许多细胞器沿着微管结合。我们检查了观察到的运动抑制的分子机制，我们证明p150（glue）抗体破坏了细胞质动力蛋白与动力蛋白的结合，也抑制了细胞质动力蛋白与细胞器的结合，相反，抗p150（glue）抗体对动力蛋白与微管的结合没有影响，也没有影响细胞质动力蛋白驱动的微管滑动。这些结果表明，细胞质动力蛋白和动力蛋白复合物之间的相互作用是膜结合囊泡轴突运输所必需的，并支持了动力蛋白可能在囊泡运输过程中作为细胞器、微管和细胞质动力蛋白之间的联系的假设。
Fast axonal transport is characterized by the bidirectional, microtubule-based movement of membranous organelles. Cytoplasmic dynein is necessary but not sufficient for retrograde transport directed From the synapse to the cell body, Dynactin is a heteromultimeric protein complex, enriched in neurons, that binds to both microtubules and cytoplasmic dynein, To determine whether dynactin is required for retrograde axonal transport, we examined the effects of anti-dynactin antibodies on organelle transport in extruded axoplasm. Treatment of axoplasm with antibodies to the p150(Glued) subunit of dynactin resulted in a significant decrease in the velocity of microtubule-based organelle transport, with many organelles bound along microtubules. We examined the molecular mechanism of the observed inhibition of motility, and we demonstrated that antibodies to p150(Glued) disrupted the binding of cytoplasmic dynein to dynactin and also inhibited the association of cytoplasmic dynein with organelles, In contrast, the anti-p150(Glued) antibodies had no effect on the binding of dynactin to microtubules nor on cytoplasmic dynein-driven microtubule gliding. These results indicate that the interaction between cytoplasmic dynein and the dynactin complex is required for the axonal transport of membrane-bound vesicles and support the hypothesis that dynactin may function as a link between the organelle, the microtubule, and cytoplasmic dynein during vesicle transport.