The Down syndrome cell adhesion molecule

Abstract

The Down syndrome cell adhesion molecules (DSCAMs) are a structurally and functionally conserved family of cell surface receptors that play important roles in nervous system organization. These receptors are expressed on both axons and dendrites where they engage in isoform-specific binding interactions between DSCAM receptors on opposing cell surfaces. Massive alternative splicing of arthropod DSCAM transcripts greatly expands the complexity of the DSCAM family by endowing these organisms with the ability to produce tens of thousands of distinct receptor isoforms that undergo homophilic binding. In addition to homophilic binding, DSCAM extracellular domains serve as receptors for other proteins such as the attractant netrin-1. These diverse interaction properties allow DSCAMs to control a variety of nervous system patterning processes including axon path-finding and targeting, neurite branch segregation, self-recognition, and neurite tiling.