FIG. 1.

E47 expression. (A) E47 mRNA level was measured by quantitative RT-PCR in 3 independent preparations of T6PNE cells and human islets from 2 different donors. (B) T6PNE and parental uninfected cells (T6PN) were assayed by immunohistochemistry for E47 (red) in the presence and absence of 4 μM tamoxifen. In the absence of tamoxifen, most cells did not have detectable E47 either in the cytoplasm or the nucleus. Some cells did have relatively weak nuclear E47, presumably due to leakiness of the modified estrogen receptor. With tamoxifen addition, nuclear E47 was greatly increased. DAPI (blue). (C) Insulin expression was responsive to the dose of tamoxifen, reaching a maximum level at 4 μM. Error bars are standard error of the mean (SEM) of 3 replicates. (D) E47 induction by tamoxifen resulted in upregulation of glucokinase, SUR-1, and MafA. Assay was done twice, and GAPDH control was equivalent between samples.