Neurons are polarized cells, with dendrites and axons that require different complements of membrane proteins to fulfill their specialized functions. Membrane proteins are synthesized in the somatodendritic domain and delivered to their target membranes via long-range vesicle transport. Most anterograde vesicle transport is mediated by kinesin motors, but it is unclear how kinesins are targeted to axons or dendrites. Two main models have been proposed to explain kinesin selectivity. In the smart motor model, kinesin selectivity is conferred by a preference of the kinesin motor domain for specific subsets of microtubules. In the cargo steering model, kinesin selectivity is modulated by the vesicular cargo to which the motor is bound. We evaluate the evidence for both models and conclude that while the smart motor model may explain axonal selectivity, cargo steering is required for dendritic selectivity. Future work will determine the relative contributions of these models to polarized transport in living neurons.

中文翻译：

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智能电机和货物转向驱动驱动蛋白介导的选择性运输。

神经元是极化的细胞，具有树突和轴突，需要不同的膜蛋白补体来实现其特定功能。膜蛋白在体树突状结构域中合成，并通过远距离囊泡运输传递至其靶膜。大多数顺行囊泡运输是由驱动蛋白驱动介导的，但尚不清楚驱动蛋白如何靶向轴突或树突。已经提出了两种主要模型来解释驱动蛋白的选择性。在智能运动模型中，针对微管的特定子集，通过选择驱动蛋白运动域，可以赋予驱动蛋白选择性。在货物转向模型中，驱动蛋白的选择性由与电动机绑定的水泡货物调节。我们评估了这两种模型的证据，并得出结论，尽管智能运动模型可以解释轴突选择性，但树突状选择性需要货物转向。未来的工作将确定这些模型对活神经元极化运输的相对贡献。