The Polo-Like Kinase (PLK; EC 2.7.11.21) family of enzymes is localized in the centrosomes or spindle pole bodies and undergo dramatic subcellular relocation during the cell cycle. They mediate G2/M transitions, activation of cdc25 and mitotic processes including centrosome maturation, bipolar spindle formation, activation of the anaphase-promoting complex (APC), chromosome segregation, and actin ring formation (cytokinesis). Deregulated activities of PLKs often result in abnormalities in centrosome duplication, maturation, and/or microtubule dynamics. PLKs also regulate the function of the Golgi complex. Deregulated expression of human PLK1 is strongly correlated with the development of many types of malignancies, and ectopic expression of PLK1 dominant negative protein leads to rapid cell death[1]. PLK3 is a multifunctional stress response protein that responses to signals induced by DNA damage and/or mitotic spindle disruption[2].