Differential induction of multiple apical and basolateral drug, toxin, and metabolite transporters in MEFs transduced with Hnf1a and Hnf4a. (A) The differential capacity of Hnf1a and Hnf4a, individually and together, to induce the transcription of a cohort of genes involved in transport was examined. (B) Expression of apical ABC transporters upon transduction. (C) Expression of basolateral ABC transporters upon transduction. (D) Expression of apical SLC transporters upon transduction. (E) Expression of basolateral SLC transporters upon transduction. The mean ± S.E.M. for each tested gene is depicted (n ≥ 3); significance of differential expression is summarized in Table 1. For convenience, results for genes within similar families are shown on a single graph. Gapdh, glyceraldehyde-3-phosphate dehydrogenase. Some localizations to apical or basolateral surfaces may be tenative, especially for SLCOs.