Resolving polarized views: septin filaments do the twist.

Septins are a highly conserved family of filamentous GTPases required for cell division in a wide range of eukaryotic organisms. In a recent issue of Nature, Vrabioiu and Mitchison use polarized fluorescence microscopy to show that septin filaments undergo a highly orchestrated rotation, from a longitudinal to circumferential orientation, coincident with splitting of the septin ring during cytokinesis (Vrabioiu and Mitchison, 2006).