Rapid assembly dynamics of the Escherichia coli FtsZ-ring demonstrated by fluorescence recovery after photobleaching.
FtsZ, the major cytoskeletal component of the bacterial cell-division machine, assembles into a ring (the Z-ring) that contracts at septation. FtsZ is a bacterial homolog of tubulin, with similar tertiary structure, GTP hydrolysis, and in vitro assembly. We used green fluorescent protein-labeled FtsZ and fluorescence recovery after photobleaching to show that the E. coli Z-ring is extremely dynamic, continually remodeling itself with a half-time of 30 s. ZipA, a membrane protein involved in cell division that colocalizes with FtsZ, was equally dynamic. The Z-ring of the mutant ftsZ84, which has 1/10 the guanosine triphosphatase activity of wild-type FtsZ in vitro, showed a 9-fold slower turnover in vivo. This finding implies that assembly dynamics are determined primarily by GTP hydrolysis. Despite the greatly reduced assembly dynamics, the ftsZ84 cells divide with a normal cell-cycle time.
Stricker
Jesse
J
Department of Cell Biology, Duke University Medical Center, Box 3709, Durham, NC 27710, USA.
Maddox
Paul
P
Salmon
E D
ED
Erickson
Harold P
HP
D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D002352:Carrier Proteins / Q000378:metabolism; D018797:Cell Cycle Proteins / Q000378:metabolism; D003598:Cytoskeletal Proteins; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism*; D029968:Escherichia coli Proteins; D005453:Fluorescence; D049452:Green Fluorescent Proteins; D008164:Luminescent Proteins / Q000235:genetics / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D013997:Time Factors
D001426:Bacterial Proteins; D002352:Carrier Proteins; D018797:Cell Cycle Proteins; D003598:Cytoskeletal Proteins; D029968:Escherichia coli Proteins; C071525:FtsZ protein, Bacteria; D008164:Luminescent Proteins; D011993:Recombinant Fusion Proteins; C103795:ZipA protein, E coli; D049452:Green Fluorescent Proteins