Positively regulates the activity of the minus-end directed microtubule motor protein dynein. Plays a central role in positioning the mitotic spindle at the bud neck during cell division. Targets cytoplasmic dynein to microtubule plus ends, thereby promoting dynein-mediated microtubule sliding along the bud cortex and consequently the movement of the mitotic spindle to the bud neck. Following plus end binding, dynein may be offloaded to the cortex by NUM1. Required for viability in the absence of the kinesin-related microtubule-dependent motor protein CIN8. Self-associates. Interacts with NDL1. May form a complex with dynein. Localizes to the plus ends of cytoplasmic microtubules. Dimerization mediated by the LisH domain may be required to activate dynein. Belongs to the WD repeat LIS1/nudF family.