Expression of adult globin protein in differentiating EBs. Adult globin proteins were analyzed by Western blot analysis. Proteins were isolated from EBs of day 6, 8, and 10 in culture. Immunoquantitation was performed using a rabbit antimouse hemoglobin serum and a goat antirabbit-IgG coupled with horseradish peroxidase in an ECL assay system. In the top panel, lane P shows the analysis protein sample from DMSO-treated MEL cells as a positive control, lanes WT show the analysis of proteins from wild-type EBs in culture of day 6, 8, and 10. Lanes ASE(-) show the analysis of proteins from ALAS-E(-) EBs in culture of day 6, 8, and 10 and lanes ASE (-) + ALA show the analysis of proteins from ALAS-E(-) EBs in culture with the addition of ALA of day 6, 8, and 10. The bottom panel is a graphic presentation of the data.