Goldberg D J, Harris D A, Lubit B W, Schwartz J H
Proc Natl Acad Sci U S A. 1980 Dec;77(12):7448-52. doi: 10.1073/pnas.77.12.7448.
Although actin is thought to participate in several types of cell motility other than muscle contraction, no direct evidence has linked it to the force-generating mechanism for fast axonal transport. We have obtained evidence for the involvement of actin by microinjecting, into the serotonergic giant cerebral neuron of Aplysia, two preparations that have been shown to depolymerize actin filaments. One is a fraction of rabbit serum containing a heat-labile gamma globulin that affects actin polymerization in a manner similar to that of cytochalasin and several proteins that are thought to regulate the length of actin filaments. The other is bovine pancreatic DNase I which binds to actin stoichiometrically. Both preparations substantially decreased the transport of storage vesicles containing [3H]serotonin. Phalloidin, a toxic fungal peptide that binds to actin filaments but stabilizes rather than depolymerizes them, did not inhibit transport. We have not yet determined whether the inhibition od transport occurs during export of [3H]serotonin from the cell body into the axon or during translocation along the axon. Nevertheless, these observations provide a promising experimental indication that actin is involved in fast axonal transport.
尽管肌动蛋白被认为除参与肌肉收缩外还参与多种细胞运动，但尚无直接证据表明它与快速轴突运输的力产生机制有关。我们通过向海兔的血清素能大脑巨型神经元中显微注射两种已被证明能使肌动蛋白丝解聚的制剂，获得了肌动蛋白参与其中的证据。一种是含有热不稳定γ球蛋白的兔血清组分，其影响肌动蛋白聚合的方式类似于细胞松弛素以及几种被认为调节肌动蛋白丝长度的蛋白质。另一种是与肌动蛋白化学计量结合的牛胰脱氧核糖核酸酶I。这两种制剂都显著降低了含有[3H]血清素的储存囊泡的运输。鬼笔环肽是一种有毒的真菌肽，它与肌动蛋白丝结合但使其稳定而非解聚，并不抑制运输。我们尚未确定运输抑制是发生在[3H]血清素从细胞体输出到轴突的过程中，还是在沿轴突转运的过程中。然而，这些观察结果提供了一个有前景的实验迹象，表明肌动蛋白参与快速轴突运输。
