Abstract
In the auditory epithelia of the cochlea, the sensory hair cells and supporting cells are arranged in a checkerboard-like pattern, but the mechanism underlying this cellular patterning was unknown. We recently found that mouse hair cells and supporting cells express the immunoglobulin-like adhesion molecules nectin-1 and -3, respectively, and that their interaction mediates the heterotypic adhesion between these two cell types. Nectins, a family of immunoglobulin-like molecules, comprising four members (nectin-1, -2, -3, and -4), promote both homophilic and heterophilic interactions between the members. Their heterophilic interactions are stronger than their homophilic interactions. When cells expressing either nectin-1 or -3 were co-cultured, they arranged themselves into a mosaic pattern. Genetic removal of nectin-1 or -3 disrupted the checkerboard pattern, inducing aberrant attachment between hair cells. These results indicate that the heterophilic interactions between nectin-1 and -3 are critical for establishing the checkerboard-like pattern of hair cells and supporting cells.
