Fig. 5. In S2 cells, Abl promotes actin accumulation while Cta promotes myosin accumulation. S2 cells are shown, and the antigens, transfections and RNAi treatments are indicated. (A) UAS-Abl::GFP fusion construct. (B-E''') Transfected cells. Arrows indicate UAS-Abl overexpressing cells in B,C; UAS-activated Cta in D; and UAS-activated Rho in E. Arrowheads indicate untransfected controls. Abl-transfected cells display elevated phosphorylated Tyr (P-Tyr; B') and concentrated actin, but show no change in Myo-P (P-Myo) expression (C). (D) Cta-transfected cells display concentrated P-Myo, but not actin. (E) Rho-transfected cells exhibit concentrated actin and P-Myo, which are organized into a central ring. (F-H') abl RNAi does not block Rho gain-of-function. (F) Control RNAi. (G,G') Control RNAi+active Rho. Notice increased Rho and concentrated actin relative to F,F'. (H,H') abl RNAi+active Rho. Rho and actin localization is similar to active Rho alone (G,G'). (I) Immunoblot showing knockdown of the Abl protein from the S2 cells shown in G-H'. Samples were non-adjacent on the same gel. Pnut, loading control; PTyr, Phospho-Tyrosine. Scale bar: 30 µm.