Microtubule-based anterograde translocator for membranous organelles, such as primary cilium and centriole. Shows a plus end- directed microtubule sliding activity in vitro. Plays a role in primary cilia formation, probably by mediating transport of proteins into primary cilia. Mediates smoothened (SMO) translocation into primary cilia in response to hedgehog morphogens. Plays a role in centriole cohesion and subdistal appendage organization and function. Regulates the formation of the subdistal appendage via recruitment of DCTN1 to the centriole. Also required for ciliary basal feet formation and microtubule anchoring to mother centriole. . This is the function of Ensembl gene identifier ENSG00000131437 (KIF3A, kinesin family member 3A).