Transient transfection analysis of proximal gsdfX and gsdfY promoter activities. (A) Different deletions of the 5′ gsdf promoters were generated (482, 1298, 1418, 1710, 2233, 2842, and 3365 bp), fused to a luciferase reporter, and analyzed for transcriptional activity after transient transfection in different medaka cell lines (B–G). The data are presented as normalized recorded Gaussia/firefly luciferase activity (see the Methods section for detailed information). For every construct, transfection was repeated six times. Error bars represent the standard deviation of the means. Light-pink shaded areas (B–D) emphasize the hAT- induced modulation of transcriptional activity. (H) Model for the sequential regulation of gsdfX and gsdfY promoter activities. See also Supplemental Data S1 for raw data.