Fig. 2: Actin filaments are required for α-catenin oligomerization.

a The GFP-αCat-C805/871 cells were cross-linked in standard conditions (Ctrl) and after 30 min with 1 μM Latrunculin B (LnB) and processed as in Fig. 1e.b Left: Western blot probed for GFP of total lysates of GFP-αCat-C805/871 cells from control culture (Ctrl); from parallel culture after 5 min-long extraction with 1% Triton X100 (Trt); after cross-linking of the control culture (XL); and after cross-linking of the Triton X100 extracted culture (Trt+XL). Right: Quantification (based on six independent experiments) of the intensities of the GFP-αCat-C805/871 monomer (relative to that in control culture) and the GFP-αCat-C805/871 adduct, a1 (relative to that in nonextracted culture). The means +/- SD are indicated by bars. Note that Triton X100 extraction reduced to ~50% the level of monomers in the control cells and nearly completely in the cross-linked cells. But it only negligibly changed the level of the adduct. Statistical significance was calculated using a two tailed Student’s t-test: ns, non-significant; *P < 0.05; ***P < 0.001; ****P < 0.0001. c Time-lapse microscopy of GFP-αCat-C805/871 cells during Triton X100 extraction. Left: The first (before extraction) and the last (after 1.5 min in Triton X100) frames from one of the obtained representative movies. Bar, 25 μM. Right: Kinetics of the GFP-αCat-C805/871 extraction obtained for AJs and for the spots outside (n = 3 taken from the same three independent movies). Data are representative as medians +/− SD.