KIF16B delivers for transcytosis

Abstract

Protein sorting pathways control correct delivery of membrane proteins to specific compartments of the plasma membrane and are required to maintain the physiological functions in all epithelia. Most clathrindependent cargoes require the adaptor protein complexes AP-1A and AP-1B for proper sorting to the basolateral plasma membrane. In this issue of The EMBO Journal, Perez Bay et al (2013) shed light on the mechanism of basal-to-apical protein transport, or transcytosis, of the transferrin receptor in natively AP-1B-deficient epithelia. In AP-1B-deficient epithelia, the transferrin receptor transcytoses through the apical recycling endosome, and requires Rab11. Furthermore, they characterize a novel and specific role for the endosomal microtubule motor Kinesin KIF16B in transferrin receptor apical transport. These findings constitute the first characterization of a specific microtubule motor involved in basal-to-apical transcytosis in epithelia. © 2013 European Molecular Biology Organization.