Centromere proteins are a group of proteins which form and/or mediate the function of centromeres, the central structures of chromosomes to which spindle fibers/microtubuli attach and pull the chromosomes apart in cell division. Currently, 9 centromere proteins are known and designated CENPA to CENP-I. Most of the centromere proteins are targets of autoantibodies, the anti-centromere antibodies.CENPB is the most important of the centromeric autoantigens: it has a molecular weight of approx. 66 kDa and plays an important role in the formation of the centromeric chromatin. CENPB antibodies are present in the sera of up to 80 % of patients with CREST syndrome Synonyms: Major centromere autoantigen B, Centromere protein B, CENP-B, CENPB