Analysis of the doxycycline-induced bicistronic protein expression.

(A) Fluorescence-activated cell sorting (FACS) analysis of EGFP expression. Overlays of histogram plots, scoring the number of cells for a given fluorescence intensity, are presented. The unfilled light gray curve corresponds to the background fluorescence profile of tTA-expressing parental cells. The unfilled and filled dark gray curves correspond to the fluorescence profiles of cells grown in the presence or absence of doxycycline, respectively. (B) Expression of themyc-tagged Cdc42N17 or Cdc42V12 proteins. Cell lysates were subjected to immunoprecipitation with anti–c-mycantibodies. Dominant-inhibitory proteins were detected by immunoblot with anti-Cdc42 antibodies. Untransfected HL-60 cells were used as control.