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Rough deal protein C-terminal region Rod, the Rough deal protein, displays a dynamic intracellular staining pattern, localising first to kinetochores in pro-metaphase, but moving to kinetochore microtubules at metaphase. Early in anaphase the protein is once again restricted to the kinetochores, where it persists until the end of telophase. This behaviour is in all respects similar to that described for ZW10, and indeed the two proteins function together, localization of each depending upon the other. These two proteins are found at the kinetochore in complex with a third, Zwilch, in both flies and humans. The C-terminus is the most conserved part of the protein. During pro-metaphase, the ZW10-Rod complex, dynein/dynactin, and Mad2 all accumulate on unattached kinetochores; microtubule capture leads to Mad2 depletion as it is carried off by dynein/dynactin; ZW10-Rod complex accumulation continues, replenishing kinetochore dynein. The continuing recruitment of the ZW10-Rod complex during metaphase may serve to maintain adequate dynein/dynactin complex on kinetochores for assisting chromatid movement during anaphase. The ZW10-Rod complex acts as a bridge whose association with Zwint-1 links Mad1 and Mad2, components that are directly responsible for generating the diffusible 'wait anaphase' signal, to a structural, inner kinetochore complex containing Mis12 and KNL-1AF15q14, the last of which has been proved to be essential for kinetochore assembly in C. elegans. Removal of ZW10 or Rod inactivates the mitotic checkpoint.
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