The NUMA protein was one of the first to be described as a cell cycle-related protein based on a distinct immunofluorescent staining pattern: in interphase, NUMA is present throughout the nucleus, and in mitosis, it localizes to the spindle apparatus (Lydersen and Pettijohn, 1980). Some patients with autoimmune disease have antibodies directed against the NUMA protein. The full-length NUMA cDNA (Compton et al., 1992; Yang et al., 1992) predicts a protein with a calculated molecular mass of about 237 kD, containing 2 globular domains separated by a coiled-coil domain of 1,485 amino acids. Wong et al. (2006) stated that the coiled-coil region of NUMA can form parallel coiled-coil dimers. By fluorescence in situ hybridization, Sparks et al. (1993) demonstrated that the NUMA1 gene is present in single copy and located on chromosome 11q13.