A fundamental characteristic of neurons is the relationship between the architecture of the polarized neuron and synaptic transmission between neurons. Intracellular membrane trafficking is paramount to establish and maintain neuronal structure; perturbation in trafficking results in defects in neurodevelopment and neurological disorders. Given the physical distance from the cell body to the distal sites of the axon and dendrites, transport of newly synthesized membrane proteins from the central cell body to their functional destination at remote, distal sites represents a conundrum. With the identification of secretory organelles in dendrites, including endoplasmic reticulum (ER) and Golgi outposts (GOs), recent studies have proposed local protein synthesis and trafficking distinct from the conventional anterograde transport pathways of the cell body. A variety of different model organisms, including Drosophila, zebrafish, and rodents, have been used to probe the organization and function of the local neuronal secretory network. Here, we review the evidence for local secretory trafficking pathways in dendrites in a variety of cell-based neuronal systems and discuss both the similarities and differences in the organization and role of the local secretory organelles, especially the GOs. In addition, we identify the gaps in the current knowledge and the potential advances using human induced pluripotent stem cells (iPSCs) in defining local membrane protein trafficking in human neurons and in understanding the molecular basis of neurological diseases.

神经元的基本特征是极化神经元的结构与神经元之间的突触传递之间的关系。细胞内膜运输对于建立和维持神经元结构至关重要。贩运活动中的摄动会导致神经发育和神经系统疾病的缺陷。给定从细胞体到轴突和树突远端位置的物理距离，新合成的膜蛋白从中央细胞体到远端远端位置的功能目的地的转运代表了一个难题。通过鉴定树突中的分泌细胞器，包括内质网（ER）和高尔基哨所（GOs），最近的研究提出了不同于细胞体常规顺行转运途径的局部蛋白质合成和运输。各种不同的模式生物，包括果蝇，斑马鱼和啮齿动物已被用来探测局部神经元分泌网络的组织和功能。在这里，我们审查了在各种基于细胞的神经元系统中树突状细胞中局部分泌运输途径的证据，并讨论了局部分泌细胞器（尤其是GOs）的组织和作用的异同。此外，我们在定义人类神经元的局部膜蛋白运输以及了解神经系统疾病的分子基础时，利用人诱导的多能干细胞（iPSC）识别了当前知识的差距和潜在的进展。