Fig. 1

Effect of Gal80 on lacZ expression in attenuation situation. a lacZ mRNA expression at the mid-saggittal plane in an embryo expressing UASx5:gal80, from mothers with four copies of Gal4GCN4. b gal80 mRNA expression in the same embryo as (a). c Merged image of expression in (a) and (b). d Network diagram, Gal4 activated gal80 and lacZ expression. Gal80 binds to Gal4, repressing gal80 and lacZ activation. e Quantification of lacZ mRNA expression in embryos without gal80 along anterior-posterior axis (given as fraction of embryo length), each colored curve represents the dorsal or ventral side of a single embryo. The average for all embryos is in black. f Average curves for lacZ expression in embryos without gal80 (n = 35), with UASx3:gal80 (n = 36), and UASx5:gal80 (n = 51). Individual curves for each embryo are shown in Additional file 1: Figure S1. g Difference, calculated as the log₁₀(p) – where p is the probability as calculated by a two-sample t-test, between the normalized intensity of lacZ without gal80 versus with UASx5:gal80 or UASx3:gal80 at a given position along the anterior-posterior axis, dashed line denotes p = 0.05. Inset shows subset of plot in (f) with arrows drawn to demonstrate how the t-test is conducted at each position along AP coordinate between the applicable normalized intensity of lacZ with gal80 and the control curve without gal80. h Box plots of AP coordinate where normalized intensity is 0.27 (see dashed lines in [f], maximum difference between no gal80 control and UASx5:gal80 [g]). Asterisk denote statistical significance (p < 0.05)