Additional file 2: Fig. S2. Ubiquitous knockdown of serotonin receptors has no effect on the climbing ability of flies. (A) qRT-PCR analysis of the mRNA expression of all five serotonin receptor knockdown lines. (B) Climbing ability of serotonin receptor knockdown flies detected by a negative geotaxis assay. Error bars are shown as the mean ± SEM. For all data, *p<0.05, **p<0.01, ***p<0.001.