Membrane trafficking mechanisms: Exocytosis and endocytosis in dendrites

Abstract

The large size of neurons poses great challenges for membrane traffic. Dendrites are often hundreds of micrometers in length, intricately branched, and studded with postsynaptic specializations. How is membrane traffic in dendrites organized to support the large size, the intricate morphology, and the spatial heterogeneity in order to create a functional neuron integrated properly into a circuit? Since dendrite form and function are disrupted when membrane traffic is disturbed, understanding membrane traffic in dendrites is important. In addition, a large number of receptors require accurate trafficking in order to participate in localized neuronal functions. The overall composition of the plasma membrane, which receptor is localized where and at what levels, is also regulated by spatially and temporally precise exo- and endocytosis. This chapter will discuss the basic cell biology of exocytic and endocytic traffic and lay out how the basic mechanisms are the same or are different in dendrites to accommodate the large size and spatial heterogeneity of neurons.