Subcellular recruitment of a RhoA ubiquitination complex by Rnd proteins

In mammalian cells, the activities of small GTP-binding proteins such as RhoA are important for coordinating their shape and their movement, but little is known about the functions for the RhoA-like proteins Rnd1-3. We have found that Rnd proteins recruit a complex comprising Bacurd2 and Cul3 which can suppress RhoA signalling by protein degradation, and we believe that Bacurd2 may operate as a signalling hub to regulate cell migration downstream of Rnd proteins in vivo. These studies will advance the novel hypothesis that RhoA signalling is influenced by protein stability within migrating cells, and our findings will improve our understanding of the role for Rnd proteins during development, as well as in normal and diseased states.