Podocyte GTPases regulate kidney filter dynamics

The way we are thinking about the kidney filtration barrier is changing from that of a static sieve into a highly dynamic structure regulated through the motility of podocyte foot processes. It has been shown in vitro that inactivation of the small GTPase RhoA causes hypermotility, whereas activation decreases motility. The current article by Wang et al. now shows that both, RhoA over- and underactivation, lead to podocyte foot process effacement and proteinuria in vivo. These data suggest that podocyte health requires a well-controlled balance between the two extremes.