---
OA_place: publisher
_id: '9992'
abstract:
- lang: eng
  text: "Blood – this is what animals use to heal wounds fast and efficient. Plants
    do not have blood circulation and their cells cannot move. However, plants have
    evolved remarkable capacities to regenerate tissues and organs preventing further
    damage. In my PhD research, I studied the wound healing in the Arabidopsis root.
    I used a UV laser to ablate single cells in the root tip and observed the consequent
    wound healing. Interestingly, the inner adjacent cells induced a\r\ndivision plane
    switch and subsequently adopted the cell type of the killed cell to replace it.
    We termed this form of wound healing “restorative divisions”. This initial observation
    triggered the questions of my PhD studies: How and why do cells orient their division
    planes, how do they feel the wound and why does this happen only in inner adjacent
    cells.\r\nFor answering these questions, I used a quite simple experimental setup:
    5 day - old seedlings were stained with propidium iodide to visualize cell walls
    and dead cells; ablation was carried out using a special laser cutter and a confocal
    microscope. Adaptation of the novel vertical microscope system made it possible
    to observe wounds in real time. This revealed that restorative divisions occur
    at increased frequency compared to normal divisions. Additionally,\r\nthe major
    plant hormone auxin accumulates in wound adjacent cells and drives the expression
    of the wound-stress responsive transcription factor ERF115. Using this as a marker
    gene for wound responses, we found that an important part of wound signalling
    is the sensing of the collapse of the ablated cell. The collapse causes a radical
    pressure drop, which results in strong tissue deformations. These deformations
    manifest in an invasion of the now free spot specifically by the inner adjacent
    cells within seconds, probably because of higher pressure of the inner tissues.
    Long-term imaging revealed that those deformed cells continuously expand towards
    the wound hole and that this is crucial for the restorative division. These wound-expanding
    cells exhibit an abnormal, biphasic polarity of microtubule arrays\r\nbefore the
    division. Experiments inhibiting cell expansion suggest that it is the biphasic
    stretching that induces those MT arrays. Adapting the micromanipulator aspiration
    system from animal scientists at our institute confirmed the hypothesis that stretching
    influences microtubule stability. In conclusion, this shows that microtubules
    react to tissue deformation\r\nand this facilitates the observed division plane
    switch. This puts mechanical cues and tensions at the most prominent position
    for explaining the growth and wound healing properties of plants. Hence, it shines
    light onto the importance of understanding mechanical signal transduction. "
acknowledged_ssus:
- _id: Bio
- _id: LifeSc
alternative_title:
- ISTA Thesis
article_processing_charge: No
author:
- first_name: Lukas
  full_name: Hörmayer, Lukas
  id: 2EEE7A2A-F248-11E8-B48F-1D18A9856A87
  last_name: Hörmayer
  orcid: 0000-0001-8295-2926
citation:
  ama: Hörmayer L. Wound healing in the Arabidopsis root meristem. 2021. doi:<a href="https://doi.org/10.15479/at:ista:9992">10.15479/at:ista:9992</a>
  apa: Hörmayer, L. (2021). <i>Wound healing in the Arabidopsis root meristem</i>.
    Institute of Science and Technology Austria. <a href="https://doi.org/10.15479/at:ista:9992">https://doi.org/10.15479/at:ista:9992</a>
  chicago: Hörmayer, Lukas. “Wound Healing in the Arabidopsis Root Meristem.” Institute
    of Science and Technology Austria, 2021. <a href="https://doi.org/10.15479/at:ista:9992">https://doi.org/10.15479/at:ista:9992</a>.
  ieee: L. Hörmayer, “Wound healing in the Arabidopsis root meristem,” Institute of
    Science and Technology Austria, 2021.
  ista: Hörmayer L. 2021. Wound healing in the Arabidopsis root meristem. Institute
    of Science and Technology Austria.
  mla: Hörmayer, Lukas. <i>Wound Healing in the Arabidopsis Root Meristem</i>. Institute
    of Science and Technology Austria, 2021, doi:<a href="https://doi.org/10.15479/at:ista:9992">10.15479/at:ista:9992</a>.
  short: L. Hörmayer, Wound Healing in the Arabidopsis Root Meristem, Institute of
    Science and Technology Austria, 2021.
corr_author: '1'
date_created: 2021-09-09T07:37:20Z
date_published: 2021-09-13T00:00:00Z
date_updated: 2026-04-08T07:11:47Z
day: '13'
ddc:
- '575'
degree_awarded: PhD
department:
- _id: GradSch
- _id: JiFr
doi: 10.15479/at:ista:9992
ec_funded: 1
file:
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  date_created: 2021-09-09T07:29:48Z
  date_updated: 2021-09-15T22:30:26Z
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file_date_updated: 2021-09-15T22:30:26Z
has_accepted_license: '1'
language:
- iso: eng
month: '09'
oa: 1
oa_version: Published Version
page: '168'
project:
- _id: 262EF96E-B435-11E9-9278-68D0E5697425
  call_identifier: FWF
  grant_number: P29988
  name: RNA-directed DNA methylation in plant development
- _id: 261099A6-B435-11E9-9278-68D0E5697425
  call_identifier: H2020
  grant_number: '742985'
  name: Tracing Evolution of Auxin Transport and Polarity in Plants
publication_identifier:
  issn:
  - 2663-337X
publication_status: published
publisher: Institute of Science and Technology Austria
related_material:
  record:
  - id: '6943'
    relation: part_of_dissertation
    status: public
  - id: '8002'
    relation: part_of_dissertation
    status: public
  - id: '6351'
    relation: part_of_dissertation
    status: public
status: public
supervisor:
- first_name: Jiří
  full_name: Friml, Jiří
  id: 4159519E-F248-11E8-B48F-1D18A9856A87
  last_name: Friml
  orcid: 0000-0002-8302-7596
title: Wound healing in the Arabidopsis root meristem
tmp:
  image: /images/cc_by_nc_nd.png
  legal_code_url: https://creativecommons.org/licenses/by-nc-nd/4.0/legalcode
  name: Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International
    (CC BY-NC-ND 4.0)
  short: CC BY-NC-ND (4.0)
type: dissertation
user_id: ba8df636-2132-11f1-aed0-ed93e2281fdd
year: '2021'
...