The plus-end directed motor protein Kinesin-1 is a major effector of microtubule-mediated transport, moving a wide range of cargo around cells. How cargo specificity is achieved and how motor transport is regulated are still not fully understood, particularly in in vivo developmental contexts. Isabel Palacios and colleagues () make use of the multiple functions of Kinesin-1 in the Drosophila oocyte to analyse how different kinesin heavy chain (KHC) domains contribute to different activities. The authors focus particularly on the tail region, which is involved in auto-inhibition and cargo binding. Although most kinesin functions are impaired in the absence of this region, some appear to be relatively unaffected. Notably, their data suggest that the auto-inhibitory IAK domain has a function independent of its auto-inhibitory activity, while the microtubule binding AMB domain is essential for transport of certain cargoes. Overall, this study showcases the distinct requirements of different cargoes for particular KHC domains - highlighting the diversity of kinesin-mediated transport mechanisms.
