Images illustrate the ring-like localization of the bacterial tubulin analog FtsZ in artificial liposomes. Shown is a DIC micrograph of a synthetic liposome in which the addition of FtsZ has created constrictions (arrows) known as Z rings that mimic its proposed role in bacterial division. The lower fluorescence micrograph reveals the concentration of FtsZ in the constrictions. See Fig 4 in Osawa et al. 2008 Science 320:792-794.