Abstract
Shugoshin-1 (Sgo1) is necessary for maintaining sister centromere cohesion and ensuring accurate chromosome segregation during mitosis. It has been reported that the localization of Sgo1 at the centromere is dependent on Bub1-mediated phosphorylation of histone H2A at T120. However, it remains uncertain whether other centromeric proteins play a role in regulating the localization and function of Sgo1 during mitosis. Here, we show that CENP-A interacts with Sgo1 and determines the localization of Sgo1 to the centromere during mitosis. Further biochemical characterization revealed that lysine and arginine residues in the C-terminal domain of Sgo1 are critical for binding CENP-A. Interestingly, the replacement of these basic amino acids with acidic amino acids perturbed the localization of Sgo1 and Aurora B to the centromere, resulting in aberrant chromosome segregation and premature chromatid separation. Taken together, these findings reveal a previously unrecognized but direct link between Sgo1 and CENP-A in centromere plasticity control and illustrate how the Sgo1-CENP-A interaction guides accurate cell division.