Regulates PLK1 kinase activity at kinetochores and promotes faithful chromosome segregation in prometaphase by bridging kinase and phosphatase activities . Phosphorylation of FIRRM by PLK1 negatively regulates its interaction with the phosphatase, PPP1CC, thus creating a negative feedback loop for maintaining proper PLK1 kinase activity during mitosis . In complex with FIGL1 may regulate homologous recombination .
Subcellular locations: Chromosome, Centromere, Kinetochore, Nucleus, Chromosome, Centromere, Midbody, Cytoplasm, Cytoskeleton, Spindle
Exhibits cell-cycle-dependent distribution during mitosis. Detected in the nucleus in interphase. Colocalizes with PLK1 to the centromeres in a nearby prometaphase cells. Relocates to the central spindle in anaphase and to the midbody in telophase cells.