Visualization of Mad2 dynamics at kinetochores, along spindle fibers, and at spindle poles in living cells.

ABSTRACT: The spindle checkpoint prevents errors in chromosome segregation by inhibiting anaphase onset until all chromosomes have aligned at the spindle equator through attachment of their sister kinetochores to microtubules from opposite spindle poles. A key checkpoint component is the mitotic arrest-deficient protein 2 (Mad2), which localizes to unattached kinetochores and inhibits activation of the anaphase-promoting complex (APC) through an interaction with Cdc20. Recent studies have suggested a catalytic model for kinetochore function where unattached kinetochores provide sites for assembling and releasing Mad2-Cdc20 complexes, which sequester Cdc20 and prevent it from activating the APC. To test this model, we examined Mad2 dynamics in living PtK1 cells that were either injected with fluoresc

SUBMITTER: Howell BJ 

PROVIDER: S-EPMC2150717 | biostudies-literature | 2000 Sep

REPOSITORIES: biostudies-literature