Dear Editor,
Chromosome movement in mitosis is orchestrated by a microtubule-based protein machinery called the mitotic spindle (Hyman and Karsenti, 1996; Compton, 2000). The bipolar organization of the mitotic spindle is essential for the accurate segregation of chromosomes into daughter cells. Defects in bipolar spindle assembly can cause chromosome instability and aneuploidy, which are frequently observed in malignant tumors (Silkworth et al., 2009; McGranahan et al., 2012). The nuclear mitotic apparatus (NuMA) is a protein critical for bipolar spindle organization primarily due to its functions in the formation of spindle poles. Dysregulation of NuMA has been reported in a number of cancer types and is associated with cancer development (Bruning-Richardson et al., 2012). Therefore, it is of great significance to understand the molecular mechanisms by which NuMA contributes to spindle pole assembly.
