1), which exhibited extensive sequence divergence with the related protein HEF1 (5).
The sodium dodecyl sulfate--polyacrylamide gel was loaded with total extracts from ZR-75-1 breast cancer cells together with ZR-75-1 cell-derived stable transfectants that overproduced BCAR1 or HEF1, and with in-vitro-produced BCAR1 and HEF1 (ITT BCAR1 and ITT HEM).
In addition to FLAG-tagged BCAR1 (ITT F-BCAR1) and HEF1 (ITT HEM), we used FLAG-tagged chimerical protein of BCAR1/HEF1 (ITT F-Hybrid) and BCAR2/Tree-132 protein as a negative control (ITT Control).
At least part of the functions of BCAR1/p130Cas cannot be substituted for by the family members HEF1 and EFS1 because homozygous deletion of the p130Cas gene causes embryonic lethality as a result of cardiovascular deficiencies (14).
On Western blots, our polyclonal chicken and rabbit antibodies directed against the central part of BCAR1 still exhibited low cross-reactivity with in-vitro-produced HEF1 protein (Fig.