Diffusion and capture permits dynamic coupling between treadmilling FtsZ filaments and cell division proteins

Nat Microbiol. 2020 Mar;5(3):407-417. doi: 10.1038/s41564-019-0657-5. Epub 2020 Jan 20.


Most bacteria accomplish cell division with the help of a dynamic protein complex called the divisome, which spans the cell envelope in the plane of division. Assembly and activation of this machinery are coordinated by the tubulin-related GTPase FtsZ, which was found to form treadmilling filaments on supported bilayers in vitro1, as well as in live cells, in which filaments circle around the cell division site2,3. Treadmilling of FtsZ is thought to actively move proteins around the division septum, thereby distributing peptidoglycan synthesis and coordinating the inward growth of the septum to form the new poles of the daughter cells4. However, the molecular mechanisms underlying this function are largely unknown. Here, to study how FtsZ polymerization dynamics are coupled to downstream proteins, we reconstituted part of the bacterial cell division machinery using its purified components FtsZ, FtsA and truncated transmembrane proteins essential for cell division. We found that the membrane-bound cytosolic peptides of FtsN and FtsQ co-migrated with treadmilling FtsZ-FtsA filaments, but despite their directed collective behaviour, individual peptides showed random motion and transient confinement. Our work suggests that divisome proteins follow treadmilling FtsZ filaments by a diffusion-and-capture mechanism, which can give rise to a moving zone of signalling activity at the division site.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bacterial Proteins / metabolism*
  • Cell Division / physiology*
  • Cell Wall / metabolism
  • Cytoskeletal Proteins / metabolism*
  • Cytoskeleton / metabolism*
  • Diffusion*
  • Escherichia coli / metabolism
  • Escherichia coli Proteins / genetics
  • Escherichia coli Proteins / metabolism*
  • GTP Phosphohydrolases
  • Membrane Proteins / metabolism


  • Bacterial Proteins
  • Cytoskeletal Proteins
  • Escherichia coli Proteins
  • FtsA protein, E coli
  • FtsN protein, E coli
  • FtsQ protein, E coli
  • FtsZ protein, Bacteria
  • Membrane Proteins
  • GTP Phosphohydrolases