FIGURE 7.

Tension and microtubules do not regulate the interaction of β-catenin with N-cadherin upon contractile activation. A, representative immunoblots illustrating the effects of blebbistatin (BLB) on the interaction of β-catenin with N-cadherin. Cells were pretreated with 30 μm blebbistatin for 15 min. They were then stimulated with 10⁻⁴ m ACh for 5 min or left unstimulated. β-Catenin/N-cadherin coupling was evaluated by coimmunoprecipitation (IP). B, β-catenin/N-cadherin ratios were normalized to the ratios in unstimulated cells not treated with blebbistatin. Data are mean ± S.E. of four independent experiments. C, representative immunoblots illustrating the effects of nocodazole on the interaction of β-catenin/N-cadherin. Cells were pretreated with 1 μm nocodazole for 15 min. They were then stimulated with 10⁻⁴ m ACh for 5 min or left unstimulated. β-Catenin/N-cadherin coupling was evaluated by coimmunoprecipitation. D, β-catenin/N-cadherin ratios were normalized to the ratios in unstimulated cells not treated with nocodazole (Noc). Data are mean ± S.E. of four independent experiments. E, untreated cells and HASM cells treated with nocodazole (1 μm, 15 min) were stained with α-tubulin antibody. a, untreated cells display a well defined microtubule structure. b, treated cells have a less defined filamentous structure. F, the fluorescence intensity in treated cells was normalized to untreated cells. Data are mean ± S.E. of 37–41 independent experiments. *, p < 0.05.