Reconstitution of contractile FtsZ rings in liposomes.

Department of Cell Biology, Duke University Medical Center, Durham, NC 27710-3709, USA.
Science (Impact Factor: 31.48). 06/2008; 320(5877):792-4. DOI: 10.1126/science.1154520
Source: PubMed

ABSTRACT FtsZ is a tubulin homolog and the major cytoskeletal protein in bacterial cell division. It assembles into the Z ring, which contains FtsZ and a dozen other division proteins, and constricts to divide the cell. We have constructed a membrane-targeted FtsZ (FtsZ-mts) by splicing an amphipathic helix to its C terminus. When mixed with lipid vesicles, FtsZ-mts was incorporated into the interior of some tubular vesicles. There it formed multiple Z rings that could move laterally in both directions along the length of the liposome and coalesce into brighter Z rings. Brighter Z rings produced visible constrictions in the liposome, suggesting that FtsZ itself can assemble the Z ring and generate a force. No other proteins were needed for assembly and force generation.

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Harold Erickson