(B) The anti-HA immunoreactive bands obtained as in (A) (arrows) have electrophoretic mobility identical to the in vitro translated cDNAs corresponding to the predicted precursor (prec) and mature (mat) APOPT1-HA protein species, synthesized using the TNT Transcription-Translation System kit (Promega). The in vitro translated products are specific, as no anti-HA immunoreactive material is visualized in the prereaction reticulocyte lysate (ret). Note that the panels are from the same filter, but different exposure times were used to better visualize the bands.