WB using Anti-Sipa1 antibody shows detection of over-expressed Sipa1 in lysates from mouse 3T3 cells transfected with Sipa1 (lane 1). Endogenous Sipa1 is detected in lane 2, which contains lysate from 3T3 cells mock-transfected with LacZGLB. Lane 3 and 4 are similar to lanes 1 and 2 except the antibody was preincubated with the immunizing peptide prior to reaction with the membrane. Primary antibody was used at 1:1250.