---
_id: '14280'
abstract:
- lang: eng
  text: "Cell division in Escherichia coli is performed by the divisome, a multi-protein
    complex composed of more than 30 proteins. The divisome spans from the cytoplasm
    through the inner membrane to the cell wall and the outer membrane. Divisome assembly
    is initiated by a cytoskeletal structure, the so-called Z-ring, which localizes
    at the center of the E. coli cell and determines the position of the future cell
    septum. The Z-ring is composed of the highly conserved bacterial tubulin homologue
    FtsZ, which forms treadmilling filaments. These filaments are recruited to the
    inner membrane by FtsA, a highly conserved bacterial actin homologue. FtsA interacts
    with other proteins in the periplasm and thus connects the cytoplasmic and periplasmic
    components of the divisome. \r\nA previous model postulated that FtsA regulates
    maturation of the divisome by switching from an oligomeric, inactive state to
    a monomeric and active state. This model was based mostly on in vivo studies,
    as a biochemical characterization of FtsA has been hampered by difficulties in
    purifying the protein. Here, we studied FtsA using an in vitro reconstitution
    approach and aimed to answer two questions: (i) How are dynamics from cytoplasmic,
    treadmilling FtsZ filaments coupled to proteins acting in the periplasmic space
    and (ii) How does FtsA regulate the maturation of the divisome?\r\nWe found that
    the cytoplasmic peptides of the transmembrane proteins FtsN and FtsQ interact
    directly with FtsA and can follow the spatiotemporal signal of FtsA/Z filaments.
    When we investigated the underlying mechanism by imaging single molecules of FtsNcyto,
    we found the peptide to interact transiently with FtsA. An in depth analysis of
    the single molecule trajectories helped to postulate a model where PG synthases
    follow the dynamics of FtsZ by a diffusion and capture mechanism. \r\nFollowing
    up on these findings we were interested in how the self-interaction of FtsA changes
    when it encounters FtsNcyto and if we can confirm the proposed oligomer-monomer
    switch. For this, we compared the behavior of the previously identified, hyperactive
    mutant FtsA R286W with wildtype FtsA. The mutant outperforms WT in mirroring and
    transmitting the spatiotemporal signal of treadmilling FtsZ filaments. Surprisingly
    however, we found that this was not due to a difference in the self-interaction
    strength of the two variants, but a difference in their membrane residence time.
    Furthermore, in contrast to our expectations, upon binding of FtsNcyto the measured
    self-interaction of FtsA actually increased. \r\nWe propose that FtsNcyto induces
    a rearrangement of the oligomeric architecture of FtsA. In further consequence
    this change leads to more persistent FtsZ filaments which results in a defined
    signalling zone, allowing formation of the mature divisome. The observed difference
    between FtsA WT and R286W is due to the vastly different membrane turnover of
    the proteins. R286W cycles 5-10x faster compared to WT which allows to sample
    FtsZ filaments at faster frequencies. These findings can explain the observed
    differences in toxicity for overexpression of FtsA WT and R286W and help to understand
    how FtsA regulates divisome maturation."
acknowledged_ssus:
- _id: Bio
- _id: LifeSc
alternative_title:
- ISTA Thesis
article_processing_charge: No
author:
- first_name: Philipp
  full_name: Radler, Philipp
  id: 40136C2A-F248-11E8-B48F-1D18A9856A87
  last_name: Radler
  orcid: '0000-0001-9198-2182 '
citation:
  ama: Radler P. Spatiotemporal signaling during assembly of the bacterial divisome.
    2023. doi:<a href="https://doi.org/10.15479/at:ista:14280">10.15479/at:ista:14280</a>
  apa: Radler, P. (2023). <i>Spatiotemporal signaling during assembly of the bacterial
    divisome</i>. Institute of Science and Technology Austria. <a href="https://doi.org/10.15479/at:ista:14280">https://doi.org/10.15479/at:ista:14280</a>
  chicago: Radler, Philipp. “Spatiotemporal Signaling during Assembly of the Bacterial
    Divisome.” Institute of Science and Technology Austria, 2023. <a href="https://doi.org/10.15479/at:ista:14280">https://doi.org/10.15479/at:ista:14280</a>.
  ieee: P. Radler, “Spatiotemporal signaling during assembly of the bacterial divisome,”
    Institute of Science and Technology Austria, 2023.
  ista: Radler P. 2023. Spatiotemporal signaling during assembly of the bacterial
    divisome. Institute of Science and Technology Austria.
  mla: Radler, Philipp. <i>Spatiotemporal Signaling during Assembly of the Bacterial
    Divisome</i>. Institute of Science and Technology Austria, 2023, doi:<a href="https://doi.org/10.15479/at:ista:14280">10.15479/at:ista:14280</a>.
  short: P. Radler, Spatiotemporal Signaling during Assembly of the Bacterial Divisome,
    Institute of Science and Technology Austria, 2023.
corr_author: '1'
date_created: 2023-09-06T10:58:25Z
date_published: 2023-09-25T00:00:00Z
date_updated: 2025-04-15T08:29:54Z
day: '25'
ddc:
- '572'
degree_awarded: PhD
department:
- _id: GradSch
- _id: MaLo
doi: 10.15479/at:ista:14280
ec_funded: 1
file:
- access_level: closed
  checksum: 87eef11fbc5c7df0826f12a3a629b444
  content_type: application/vnd.openxmlformats-officedocument.wordprocessingml.document
  creator: pradler
  date_created: 2023-10-04T10:11:53Z
  date_updated: 2024-10-05T22:30:03Z
  embargo_to: open_access
  file_id: '14390'
  file_name: PhD Thesis_Philipp Radler_20231004.docx
  file_size: 114932847
  relation: source_file
- access_level: open_access
  checksum: 3253e099b7126469d941fd9419d68b4f
  content_type: application/pdf
  creator: pradler
  date_created: 2023-10-04T10:11:21Z
  date_updated: 2024-10-05T22:30:03Z
  embargo: 2024-10-04
  file_id: '14391'
  file_name: PhD Thesis_Philipp Radler_20231004.pdf
  file_size: 37838778
  relation: main_file
file_date_updated: 2024-10-05T22:30:03Z
has_accepted_license: '1'
keyword:
- Cell Division
- Reconstitution
- FtsZ
- FtsA
- Divisome
- E.coli
language:
- iso: eng
month: '09'
oa: 1
oa_version: Published Version
page: '156'
project:
- _id: 2595697A-B435-11E9-9278-68D0E5697425
  call_identifier: H2020
  grant_number: '679239'
  name: Self-Organization of the Bacterial Cell
- _id: fc38323b-9c52-11eb-aca3-ff8afb4a011d
  grant_number: P34607
  name: In vitro reconstitution of bacterial cell division
- _id: 2596EAB6-B435-11E9-9278-68D0E5697425
  grant_number: ALTF 2015-1163
  name: Synthesis of bacterial cell wall
- _id: 259B655A-B435-11E9-9278-68D0E5697425
  grant_number: LT000824/2016
  name: Reconstitution of bacterial cell wall synthesis
publication_identifier:
  isbn:
  - 978-3-99078-033-6
  issn:
  - 2663-337X
publication_status: published
publisher: Institute of Science and Technology Austria
related_material:
  record:
  - id: '10934'
    relation: research_data
    status: public
  - id: '11373'
    relation: part_of_dissertation
    status: public
  - id: '7387'
    relation: part_of_dissertation
    status: public
status: public
supervisor:
- first_name: Martin
  full_name: Loose, Martin
  id: 462D4284-F248-11E8-B48F-1D18A9856A87
  last_name: Loose
  orcid: 0000-0001-7309-9724
title: Spatiotemporal signaling during assembly of the bacterial divisome
tmp:
  image: /images/cc_by.png
  legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode
  name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)
  short: CC BY (4.0)
type: dissertation
user_id: 8b945eb4-e2f2-11eb-945a-df72226e66a9
year: '2023'
...