The kinesin KIF21B participates in the cell surface delivery of γ2 subunit-containing GABAA receptors

KIF21B, a kinesin family (KIF) protein, is a plus end-directed microtubule motor. The KIF21B gene is highly expressed in neuronal tissue and spleen and is a susceptibility locus for multiple sclerosis. KIF21B motility is regulated through TRIM3, a member of the cytoskeleton-associated-recycling or transport (CART) complex, involved in vesicular receptor recycling. Here we show that the GABA(A) receptor gamma 2-subunit co-precipitates and co-localizes with KIF21B in cultured hippocampal neurons. Knockdown of KIF21B gene expression through small hairpin (sh) RNA reduces the number of gamma 2-subunit-containing GABA(A) receptor (GABA(A)Rs) clusters in neurites and at the cell surface. Our data suggest that KIF21B participates in the delivery of GABA(A)R transport vesicles into dendrites. (C) 2014 The Authors. Published by Elsevier GmbH.