Fig. 1

A GstO2 overexpression by elav-Gal4, a neuron-specific driver, partially restored the reduced locomotor activity in TAF15-overexpressing flies. The movement of third instar larvae on the agar plate was monitored for 90 s, and the average distance of the larval trails was calculated (n = 10 for each genotype). The error bars represent the mean ± standard deviation. Statistical significance was determined using one-way analysis of variance (ANOVA; *, p < 0.05; ***, p < 0.001; ns not significant). B Representative images of neuromuscular junction boutons labeled with anti-horseradish peroxidase at muscle 6/7 of segment 3 and quantification of the total number of boutons. TAF15 expression in the neurons of flies resulted in a significant reduction in the number of boutons. GstO2 expression in neuronal cells partially improved the reduced synaptic bouton number in TAF15-expressing flies. Error bars represent the mean ± standard deviation (n ≤ 7 for each genotype). Experimental significance was determined using one-way ANOVA (*p < 0.05; ***p < 0.001; ns not significant). C TAF15 levels in GstO2 co-expressing fly heads. TAF15 and GstO2 co-expression in neuronal cells resulted in a significant reduction in TAF15 levels. β-actin was used as a loading control. Error bars represent mean ± standard deviation of three independent experiments. Quantification of TAF15 levels was normalized to β‐actin (n = 3, independent preparations). Experimental significance was determined using Student’s t test (**, p < 0.01). D TAF15 mRNA expression in the heads of TAF15-expressing flies. GstO2 expression did not affect TAF15 mRNA levels. rp49 was used as a loading control. Quantified TAF15 mRNA levels were normalized to the rp49 levels. Error bars represent the mean ± standard deviation of three independent experiments. The significance was determined using Student’s t test (ns not significant). E Both cytoplasmic and nuclear TAF15 levels were reduced by GstO2 overexpression in neuronal cells. Quantification of TAF15 levels normalized to α-tubulin (the cytoplasmic marker) and histone H3 (the nuclear marker) (n = 3, independent preparations). The error bars represent the standard deviation. Experimental significance was determined using Student’s t test (*, p < 0.05). F Soluble and insoluble fractions isolated from adult heads of the indicated genotypes were analyzed using immunoblotting. Both soluble and insoluble TAF15 levels were decreased by GstO2 overexpression. β-actin was used as a loading control. Quantification of TAF15 levels was normalized to β‐actin. The error bars represent the standard deviation of three independent experiments. Statistical significance was determined using Student’s t test (*, p < 0.05; **, p < 0.01). G 2′,7′-dichlorofluorescein (DCF) fluorescence (green) indicates reactive oxygen species (ROS). Increased ROS production in TAF15-expressing flies compared with that in the control flies. GstO2 co-expression suppressed ROS production in TAF15-expressing flies. Quantification of DCF fluorescence intensity in whole brains (dotted line) was performed using ImageJ software and normalized to the value of control flies. Experimental significance was determined using one-way ANOVA (***, p < 0.001; ns not significant; n ≤ 9 for each genotype)