Background information
The breakpoint cluster region protein (Bcr) is best know to be involved in genomic translocation with fusion partner Abl (Cbr-Abl) causing chronic myelogenous leukemia (CML). This 160 kDa protein contains a serine/threonine kinase domain, an SH2 binding domain, a GTP/GDP exchange domain and a C-term domain which functions as a GTPase activating protein for p21rac and CDC42. Additionally, Bcr is involved in signal transduction and can down regulate Ras mediated cell signaling.