Architecture of the ring formed by the tubulin homologue FtsZ in bacterial cell division

  1. Piotr Szwedziak
  2. Qing Wang
  3. Tanmay A M Bharat
  4. Matthew Tsim
  5. Jan Löwe  Is a corresponding author
  1. MRC Laboratory of Molecular Biology, United Kingdom

Abstract

Membrane constriction is a prerequisite for cell division. The most common membrane constriction system in prokaryotes is based on the tubulin homologue FtsZ, whose filaments in E. coli are anchored to the membrane by FtsA and enable formation of the Z ring and divisome. The precise architecture of the FtsZ ring has remained enigmatic. Here, we report three-dimensional arrangements of FtsZ and FtsA filaments in C. crescentus and E. coli cells and inside constricting liposomes by means of electron cryomicroscopy and cryotomography. In vivo and in vitro, the Z-ring is composed of a small, single-layered band of filaments parallel to the membrane, creating a continuous ring through lateral filament contacts. Visualisation of the in vitro reconstituted constrictions as well as a complete tracing of the helical paths of the filaments with a molecular model favour a mechanism of FtsZ-based membrane constriction that is likely to be accompanied by filament siding.

Article and author information

Author details

  1. Piotr Szwedziak

    Division of Structural Studies, MRC Laboratory of Molecular Biology, Cambridge, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  2. Qing Wang

    DIvision of Structural Studies, MRC Laboratory of Molecular Biology, Cambridge, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  3. Tanmay A M Bharat

    Division of Structural Studies, MRC Laboratory of Molecular Biology, Cambridge, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  4. Matthew Tsim

    Division of Structural Studies, MRC Laboratory of Molecular Biology, Cambridge, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  5. Jan Löwe

    DIvision of Structural Studies, MRC Laboratory of Molecular Biology, Cambridge, United Kingdom
    For correspondence
    jyl@mrc-lmb.cam.ac.uk
    Competing interests
    The authors declare that no competing interests exist.

Reviewing Editor

  1. Werner Kühlbrandt, Max Planck Institute of Biophysics, Germany

Version history

  1. Received: September 3, 2014
  2. Accepted: December 8, 2014
  3. Accepted Manuscript published: December 9, 2014 (version 1)
  4. Version of Record published: January 6, 2015 (version 2)

Copyright

© 2014, Szwedziak et al.

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.

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  1. Piotr Szwedziak
  2. Qing Wang
  3. Tanmay A M Bharat
  4. Matthew Tsim
  5. Jan Löwe
(2014)
Architecture of the ring formed by the tubulin homologue FtsZ in bacterial cell division
eLife 3:e04601.
https://doi.org/10.7554/eLife.04601

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https://doi.org/10.7554/eLife.04601

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