(H) Upper panel, H2B substrate phosphorylation by dS6K from larval protein extracts. Ubiquitous induction of UAS-DHR3 RNAi, using either a daughterless-Gal4 (da>Ri) or an actin-Gal4 (ac>Ri) driver, provoked a drop in dS6K activity, as compared with control drivers alone (da, ac). Middle and lower panels are western blots detecting dS6K and α-tubulin, respectively. 