Kinetochore dynein: its dynamics and role in the transport of the Rough deal checkpoint protein

We describe the dynamics of kinetochore dynein-dynactin in living Drosophil a embryos and examine the effect of mutant dynein on the metaphase checkpoi nt. A functional conjugate of dynamitin with green fluorescent protein accu mulates rapidly at prometaphase kinetochores, and subsequently migrates off kinetochores towards the poles during late prometaphase and metaphase. Thi s behaviour is seen for several metaphase checkpoint proteins, including Ro ugh deal (Rod). In neuroblasts, hypomorphic dynein mutants accumulate in me taphase and block the normal redistribution of Rod from kinetochores to mic rotubules. By transporting checkpoint proteins away from correctly attached kinetochores, dynein might contribute to shutting off the metaphase checkp oint, allowing anaphase to ensue.