Sorting Nexin 17 Interacts Directly with Kinesin Superfamily KIF1B beta Protein

ABSTRACT

KIF1B beta is a member of the Kinesin superfamily proteins (KIFs), which are microtubule-dependent molecular motors that are involved in various intracellular organellar transport processes. KIF1B beta is not restricted to neuronal systems, however, is widely expressed in other tissues, even though the function of KIF1B beta is still unclear. To elucidate the KIF1B beta-binding proteins in non-neuronal cells, we used the yeast two-hybrid system, and found a specific interaction of KIF1B beta and the sorting nexin (SNX) 17. The C-terminal region of SNX17 is required for the binding with KIF1B beta. SNX17 protein bound to the specific region of KIF1B beta (813-916. aa), but not to other kinesin family members. In addition, this specific interaction was also observed in the Glutathione S-transferase pull-down assay. An antibody to SNX17 specifically co-immunoprecipitated KIF1B beta associated with SNX17 from mouse brain extracts. These results suggest that SNX17 might be involved in the KIF1B beta-mediated transport as a KIF1B beta adaptor protein.