Vale R D, Schnapp B J, Reese T S, Sheetz M P
Cell. 1985 Feb;40(2):449-54. doi: 10.1016/0092-8674(85)90159-x.
Cytoplasmic filaments, separated from the axoplasm of the squid giant axon and visualized by video-enhanced differential interference contrast microscopy, support the directed movement of organelles in the presence of ATP. All organelles, regardless of size, move continuously along isolated transport filaments at 2.2 +/- 0.2 micron/sec. In the intact axoplasm, however, movements of the larger organelles are slow and saltatory. These movements may reflect a resistance to movement imposed by the intact axoplasm. The uniform rate of all organelles along isolated transport filaments suggests that a single type of molecular motor powers fast axonal transport. Organelles can attach to and move along more than one filament at a time, suggesting that organelles have multiple binding sites for this motor.
从枪乌贼巨大轴突的轴浆中分离出的细胞质细丝，通过视频增强差分干涉对比显微镜观察发现，在三磷酸腺苷（ATP）存在的情况下，这些细丝支持细胞器的定向移动。所有细胞器，无论大小，都以2.2±0.2微米/秒的速度沿着分离的运输细丝持续移动。然而，在完整的轴浆中，较大细胞器的移动缓慢且呈跳跃式。这些移动可能反映了完整轴浆对移动施加的阻力。所有细胞器沿着分离的运输细丝移动的速率一致，这表明单一类型的分子马达驱动快速轴突运输。细胞器可以同时附着在一根以上的细丝上并沿着其移动，这表明细胞器对这种马达有多个结合位点。
