Sodium Channel Voltage Gated Type II Beta (SCN2b)

SCN2b is a 186-residue glycoprotein that contains an extracellular N-terminal domain with similarity to the neural adhesion molecule contactin, as well as a single transmembrane domain.Expression of the isolated beta-2 intracellular domain increased the mRNA and protein levels of the Nav1.1 alpha subunit (SCN1A) in human and rodent neuroblastoma cells. Brains of BACE1-transgenic mice and Alzheimer disease patients with elevated BACE1 levels exhibited elevated levels of beta-2 C-terminal fragment and Nav1.1 protein. However, in both rodent neuroblastoma cells and adult hippocampal neurons from BACE1-transgenic mice, Nav1.1 accumulated inside the cell rather than at the cell surface, and there was marked reduction in Nav1-mediated sodium current density.