Neuronal polarization and growth are developmental processes that occur during neuronal cell differentiation. The molecular signaling mechanisms involved in these events in in vivo mammalian brain remain unclear. Also, cellular events of the neuronal polarization process within a given neuron are thought to be constituted of many independent intracellular signal transduction pathways (the “tug-of-war” model). However, in vivo results suggest that such pathways should be cooperative with one another among a given group of neurons in a region of the brain. Lipid rafts, specific membrane domains with low fluidity, are candidates for the hotspots of such intracellular signaling. Among the signals reported to be involved in polarization, a number are thought to be present or translocated to the lipid rafts in response to extracellular signals. As part of our analysis, we discuss how such novel molecular mechanisms are combined for effective regulation of neuronal polarization and growth, focusing on the significance of the lipid rafts, including results based on recently introduced methods.

神经元极化和生长是在神经元细胞分化过程中发生的发育过程。这些事件中涉及的分子信号传导机制体内哺乳动物的大脑仍不清楚。同样，给定神经元内神经元极化过程的细胞事件被认为是由许多独立的细胞内信号转导途径组成的（“拔河比赛”模型）。然而，体内结果表明，这种通路应该在大脑区域中给定的一组神经元之间相互协作。脂质筏，低流动性的特定膜结构域，是此类细胞内信号传导热点的候选者。在据报道参与极化的信号中，响应于细胞外信号，许多信号被认为存在或转移至脂质筏。作为我们分析的一部分，我们将讨论如何结合这种新颖的分子机制来有效调节神经元极化和生长，重点关注脂质筏的重要性，包括基于最近介绍的方法得出的结果。