Rho GTPases play central roles in a wide variety of cellular processes, 
including cytoskeletal dynamics, cell adhesion and cell polarity. RhoU and RhoV 
are Rho GTPases that have some atypical properties compared with classical Rho 
family members, such as the presence of N- and C-terminal extension regions, 
unusual GDP/GTP cycling and post-translational modification by palmitoylation 
but not prenylation. Their activity and localization is regulated by the 
N-terminal and C-terminal regions, and so far no GEFs or GAPs have been 
identified for them. Similar to Rac and Cdc42, they interact with PAK 
serine/threonine kinases, and in the case of PAK4, this interaction leads to 
RhoU protein stabilization. In cells, RhoU and RhoV alter cell shape and cell 
adhesion, which probably underlies some of the phenotypes reported for these 
proteins in vivo, for example in heart development and epithelial morphogenesis. 
However, the molecular basis for these functions of RhoU and RhoV remains to be 
characterized.