Down Syndrome Cell Adhesion Molecule (DSCAM)

Dscam binds directly to both the SH2 and SH3 domains of Dock. Genetic studies revealed that Dscam, Dock, and Pak, a serine/threonine kinase, act together to direct pathfinding of Bolwig's nerve, which contains a subclass of sensory axons, to an intermediate target in the embryo. Dscam also is required for the formation of axon pathways in the embryonic central nervous system. cDNA and genomic analyses revealed the existence of multiple forms of Dscam with a conserved architecture containing variable immunoglobulin and transmembrane domains. Alternative splicing can potentially generate more than 38,000 Dscam isoforms in Drosophila. The authors suggested that this molecular diversity may contribute to the specificity of neuronal connectivity.