Loss of E-cadherin–mediated cell–cell contact in ES cells induces reversible actin cytoskeleton rearrangement in the absence of up-regulation of EMT-associated transcripts. (a) D3 ES cells cultured in ES cell medium containing FCS+LIF on gelatin-treated plates were treated with either (i) control antibody (cAb) or (ii) E-cadherin–neutralizing antibody (nAb) DECMA-1 for 24 h and actin cytoskeleton arrangement determined using Texas Red–conjugated phalloidin and fluorescent microscopy analysis. (iii) DECMA-1 antibody was removed from the treated cells, and actin cytoskeleton arrangement assessed after 3 d as described above. Bar, 10 μm. (b) D3 ES cells cultured for six passages (∼12 d) in FCS+LIF and either control antibody (cAb) or neutralizing antibody DECMA-1 (nAb) were assessed for DAPI, OCT-4 and E-cadherin protein expression by immunofluorescent microscopy. Bar, 10 μm. (c) Analysis of EMT-associated transcripts was determined by RT-PCR in D3 ES cells treated with either (i) control (cAb) or (ii) DECMA-1 (nAb) antibody for 72 h (C, control; β-tub, β-tubulin). Similar results were also obtained with MESC20 ES cells.