The Plant SNX Family and Its Role in Endocytosis

Separation of functions within the cytoplasm of the eukaryotic cell has resulted in the development of a highly dynamic network of membranous compartments. Among them, the endosomes represent a crossing point for the major cellular trafficking pathways. Indeed, they are responsible for the communication between the cellular compartments, as well as between the cell and its environment, through the regulation of signalling networks and transport of material. The proteins from the sorting nexin (SNX) family have an established role as major regulators of endosomal protein transport in mammals, insects, worms, and yeast. By contrast, research on plant SNXs has been initiated relatively recently. Despite that, the accumulated knowledge suggests that plant SNXs may have evolved different mechanisms of action and might work in a different protein complex environment, compared to their yeast and animal counterparts. In this chapter, we highlight both common and specific characteristics of plant SNX protein function and regulation in comparison to the well-studied mammalian SNX machinery.