Analysis of Fox-2 isoforms expression during erythroid differentiation of mouse fetal liver cells. (A) Flow cytometry of cultured fetal liver cells at 0, 1, and 2 days in erythroid-differentiation medium. Cells were double-stained for a PE-conjugated anti-TER119 mAb and an FITC-conjugated anti-CD71 mAb and analyzed by flow cytometry. Axes indicate relative logarithmic fluorescence units for PE (x-axis) and FITC (y-axis). Regions 1 to 5 are defined by characteristic staining pattern of cells, including CD71^medTER119^low, CD71^highTER119^low, CD71^highTER119^high, CD71^medTER119^high, and CD71^lowTER119^high, respectively. (B) Fox-2A and -2F isoforms expression analyzed by RT-PCR and Western blot analyses (bottom panel). Hprt1 serves as an internal control for RT-PCR. (C) Relative expression of Fox-2A and Fox-2F in erythroid differentiation of fetal liver cells. Semiquantitative RT-PCR products were scanned and analyzed by the ChemiImager 5500 system (Alpha Innotech Co, San Leandro, CA). Day-0 and day-2 cells were analyzed for expression of mFox-2 isoforms. The bar graph represents the relative levels of mFox-2 mRNA in the day 0 and day 2 cells. Day 2 mFox-2 levels are expressed relative to those in day 0 cells and normalized with Hprt1. Error bars represent standard deviation. Day 0 was taken as 1.