I'm a little confused over the roles of RhoA, Rac and Cdc42.
From this text it would seem that when cadherins form a junction with one another RhoA is inhibited, whilst Cdc42 and Rac is activated.
We have demonstrated in previous studies that cadherin signaling suppresses RhoA activity and activates Rac1.
However from the same paper:
In fibroblasts, Rac1 and Cdc42 activation result in lamellipodial and filopodial extension, respectively, and RhoA regulates stress fiber and focal adhesion formation (3). In epithelial cells, Rac1 and Cdc42 activity are required for cadherin-mediated adhesion
I must be understanding this incorrectly but I would have thought that a cell which is not receiving cadherin signalling, i.e. is therefore alone, would be better off up regulating lamellipodia and filopodia in an attempt to find other cells in the system? And conversely cells which are receiving cadherin signals should up regulate stress fibres to keep in place and be nonmotile as part of the system they're in?