Microtubule disruption dephosphorylates p120 and stimulates cadherin-based adhesion in Colo 205 cells.

<p>(A-F) Brightfield microscopy of non-adhesive and adhesion-activated Colo 205 cells. Scale bar = 50 μm. (A-C) Parental or p120 knockdown cells were treated with either 10 μM nocodazole or an equal volume of DMSO for 1.5 hours. (D-F) Parental cells were pre-treated with 10 μM taxol for 2 hours then treated with 2 μg/mL 19A11 activating E-cadherin mAb for 4 hours. (G) Colo 205 cells expressing EB1-EGFP were treated with various concentrations of nocodazole and imaged at 10 minutes via fluorescent confocal microscopy. Scale bar = 5 μm. The same cells were then imaged by brightfield microscopy (scale bar = 50 μM) after 2 hours of treatment to examine the extent of adhesion activation, then fixed in methanol and immunostained for α-tubulin to examine the extent of microtubule disruption (scale bar = 5 μm). (H) Cells were treated for 1.5 hours with various concentrations of nocodazole then lysed in 1% triton x-100. Samples were resolved on 6% SDS-PAGE with 20 μM Phos-tag reagent then visualized via Western blotting. Red stars = higher molecular weight in non-activated samples, cyan stars = lower molecular weight in activated samples.