DN impact of AIRE ^C337F on WT AIRE-mediated gene transcription. HEK-293T cell lines were transfected with plasmids encoding either WT AIRE or AIRE^R257X, AIRE^C311Y or AIRE^C337F variants alone, or equal amounts WT AIRE together with AIRE^R257X, AIRE^C311Y, or AIRE^C337F. (A and B) Transcriptional activity was assessed by measuring expression levels of (A) known AIRE-regulated genes KRT14, IGFL1, S100A8, APOA4, and INS or (B) non-AIRE-regulated genes CCHN and PRMT3. Data are presented as mean fold-change in expression relative to cells transfected with WT 100% used as the calibrator sample (dotted line). Error bars represent the standard error of the mean from three independent experiments.