To reorganize the cell’s skeleton, small G-proteins activate proteins involved in actin nucleation. However, in trafficking processes when actin is required, it is not clear how these small G-proteins interact with actin nucleators on internal membranes. Ashley Russo and colleagues in the lab of ASCB member Kenneth Campellone at University of Connecticut investigated the role of G-proteins in the Rho, Arf, and Rab families in regulating WHAMM (WASP Homolog associated with Actin, Membranes, and Microtubules), a protein involved in promoting actin nucleation. They found that Rab1 recruited WHAMM to dynamic tubulo-vesicular structures and regulated WHAMM-mediated actin nucleation. Published in MBoC.