Mutations in the Drosophila melanogaster zw10 gene, which encodes a co
nserved, essential kinetochore component, abolish the ability of dynei
n to localize to kinetochores. Several similarities between the behavi
or of ZW10 protein and dynein further support a role for ZW10 in the r
ecruitment of dynein to the kinetochore: (a) in response to bipolar te
nsion across the chromosomes, both proteins mostly leave the kinetocho
re at metaphase, when their association with the spindle becomes appar
ent; (b) ZW10 and dynein both bind to functional neocentromeres of str
ucturally acentric minichromosomes; and (c) the localization of both Z
W10 and dynein to the kinetochore is abolished in cells mutant for the
gene rough deal. ZW10's role in the recruitment of dynein to the kine
tochore is likely to be reasonably direct, because dynamitin, the p50
subunit of the dynactin complex, interacts with ZW10 in a yeast two-hy
brid screen. Since in zw10 mutants no defects in chromosome behavior a
re observed before anaphase onset, our results suggest that dynein at
the kinetochore is essential for neither microtubule capture nor congr
ession to the metaphase plate. Instead, dynein's role at the kinetocho
re is more likely to be involved in the coordination of chromosome sep
aration and/or poleward movement at anaphase onset.