Paschal B M, Vallee R B
Cell Biology Group, Worcester Foundation for Experimental Biology, Shrewsbury, Massachusetts 01545.
Nature. 1987;330(6144):181-3. doi: 10.1038/330181a0.
Microtubules are involved in several forms of intracellular motility, including mitosis and organelle movement. Fast axonal transport is a highly ordered form of organelle motility that operates in both the anterograde (outwards from the cell body) and retrograde (from the periphery towards the cell body) direction. Similar microtubule-associated movement is observed in non-neuronal cells, and might be involved in secretion, endocytosis and the positioning of organelles within the cell. Kinesin is a mechanochemical protein that produces force along microtubules in an anterograde direction. We recently found that the brain microtubule-associated protein MAP 1C (ref. 7) is a microtubule-activated ATPase and, like kinesin, can translocate microtubules in an in vitro assay for microtubule-associated motility. MAP 1C seemed to be related to the ciliary and flagellar ATPase, dynein, which is thought to produce force in a direction opposite to that observed for kinesin. Here we report that MAP 1C, in fact, acts in a direction opposite to kinesin, and has the properties of a retrograde translocator.
微管参与多种形式的细胞内运动，包括有丝分裂和细胞器移动。快速轴突运输是一种高度有序的细胞器运动形式，可沿顺行（从细胞体向外）和逆行（从外周向细胞体）方向进行。在非神经元细胞中也观察到类似的微管相关运动，其可能参与细胞内的分泌、胞吞作用以及细胞器的定位。驱动蛋白是一种机械化学蛋白，可沿微管在顺行方向产生力。我们最近发现，脑微管相关蛋白MAP 1C（参考文献7）是一种微管激活的ATP酶，并且与驱动蛋白一样，在微管相关运动的体外试验中能使微管移位。MAP 1C似乎与纤毛和鞭毛ATP酶动力蛋白有关，动力蛋白被认为能在与驱动蛋白相反的方向产生力。在此我们报告，实际上MAP 1C的作用方向与驱动蛋白相反，并且具有逆行转运体的特性。
