Fig. 5. POPX2 blocks the effect of dominant-negative mDia. (A) Flag-mDia-DN was transfected either with or without POPX2 into HeLa cells. The cells were fixed and immunostained with anti-Flag antibodies and rhodamine-coupled phalloidin. Cells transfected with just mDia-DN alone showed loss of stress fibres. Cells co-transfected with mDia-DN and POPX2 still contained stress fibres. (B) Transfection with different cDNAs and detection of stress fibres were performed as in A. The phenotype was scored by analyzing at least 100 cells per transfection. Each transfection was repeated three times. Lane 1, GFP; 2, mDia-DN; 3, POPX2; 4, POPX2m; 5, mDia-DN + POPX2; 6, mDia-DN + POPX2m; 7, mDia-DN + KID. Scale bars: 10 µm.