Abstract
Axons and dendrites of developing neurons establish distributed innervation patterns enabling precise discrimination in sensory systems. We describe the role of the extracellular matrix molecule, laminin β2, interacting with the CaV2.2 calcium channel in establishing appropriate sensory innervation. In vivo, CaV2.2 is expressed on the growth cones of Xenopus laevis sensory neurites and laminin β2 is expressed in the skin. Culturing neurons on a laminin β2 substrate inhibits neurite outgrowth in a specific and calcium-dependent manner. Blocking signaling between laminin β2 and CaV2.2 leads to increased numbers of sensory terminals in vivo. These findings suggest that interactions between extracellular matrix molecules and calcium channels regulate connectivity in the developing nervous system.