BUB1 (Bub1, Bub-1, BublL, Budding uninhibited by benzimidazoles 1-like)

Chromosome segregation and mitotic checkpoints are regulated by various proteins among them are BUB1 and BUBR1/BUB1B (Budding Uninhibited by Benzimidazoles 1). During mitosis both BUB1 and BUBR1 proteins are localized to kinetochores and inhibit the anaphase stage until all chromosomes are correctly attached to the spindle. These proteins were found due to their homology to Bub1 protein from yeast. Human BUBR1 contains CD1 and CD2 domains that are found in human, mouse and yeast BUB1 (3-5). The human and mouse BUBR1 proteins are 29% identical in these regions. The kinetochore localization and Bub3 binding is found in the CD1 region while the kinase domain is found in the CD2 domain. While both human and mouse BUB1 contain a nuclear localization site between CD1 and CD2 regions, the yeast protein does not contain this site. BUB1 is expressed in many tissues with the highest expression in testis and thymus, lower expression in colon and small intestine and very low expression in spleen and ovary. BUB1 expression is in correlation with the expression of MAD2, another human spindle assembly checkpoint protein (3-5). BUBR1 is mainly expressed in testis, thymus and bone marrow while in differentiated tissues such as brain, heart and muscle the expression is low (5). Applications: Suitable for use in ELISA, Western Blot, Immunoprecipitation and Immunocytochemistry. Other applications not tested. Recommended Dilution: Immunocytochemistry: 4-8ug/ml. Optimal dilutions to be determined by the researcher. Hybridoma: Mouse myeloma SP2/0 cells and splenocytes from BALB/c mice Storage and Stability: May be stored at 4 degrees C for short-term only. Aliquot to avoid repeated freezing and thawing. Store at -20 degrees C. Aliquots are stable for at least 12 months. For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap.