Reconstitution of self-organizing protein gradients as spatial cues in cell-free systems

  1. Katja Zieske
  2. Petra Schwille  Is a corresponding author
  1. Max Planck Institute of Biochemistry, Germany

Abstract

Intracellular protein gradients are significant determinants of spatial organization. However, little is known about how protein patterns are established, and how their positional information directs downstream processes. We have accomplished the reconstitution of a protein concentration gradient that directs the assembly of the cell division machinery in E.coli from the bottom-up. Reconstituting self-organized oscillations of MinCDE proteins in membrane-clad soft-polymer compartments, we demonstrate that distinct time-averaged protein concentration gradients are established. Our minimal system allows to study complex organizational principles, such as spatial control of division site placement by intracellular protein gradients, under simplified conditions. In particular, we demonstrate that FtsZ, which marks the cell division site in many bacteria, can be targeted to the middle of a cell-like compartment. Moreover, we show that compartment geometry plays a major role in Min gradient establishment, and provide evidence for a geometry-mediated mechanism to partition Min proteins during bacterial development.

Article and author information

Author details

  1. Katja Zieske

    Max Planck Institute of Biochemistry, Martinsried, Munich, Germany
    Competing interests
    The authors declare that no competing interests exist.
  2. Petra Schwille

    Max Planck Institute of Biochemistry, Martinsried, Munich, Germany
    For correspondence
    schwille@biochem.mpg.de
    Competing interests
    The authors declare that no competing interests exist.

Reviewing Editor

  1. Mohan Balasubramanian, University of Warwick, United Kingdom

Publication history

  1. Received: July 10, 2014
  2. Accepted: September 30, 2014
  3. Accepted Manuscript published: October 1, 2014 (version 1)
  4. Version of Record published: November 3, 2014 (version 2)

Copyright

© 2014, Zieske & Schwille

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. Katja Zieske
  2. Petra Schwille
(2014)
Reconstitution of self-organizing protein gradients as spatial cues in cell-free systems
eLife 3:e03949.
https://doi.org/10.7554/eLife.03949

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