---
OA_embargo: '12'
OA_place: publisher
_id: '19722'
abstract:
- lang: eng
  text: "As root epidermal cells progress from a phase of elongation to differentiation,
    their\r\ncortical microtubule (MT) arrays exhibit a transversal-to-longitudinal
    reorientation. The\r\nhormone cytokinin, a key regulator of root development,
    facilitates these cytoskeletal\r\nchanges. However, the molecular mechanisms underlying
    hormone-mediated MT\r\nreorientation during root development are still unknown.
    Here, we find that MT reorientation\r\nin root cells differs from the existing
    model in hypocotyl cells, as it does not rely on MT plusend rescue. We show that
    cytokinin facilitates MT array reorganization during cell\r\ndifferentiation by
    promoting katanin’s (KTN1) severing activity, and by modulating KTN1’s\r\nassociation
    with microtubules. Cytokinin regulates SPIRAL2 (SPR2) in a phosphorylationdependent
    manner, directing its localization to, and stabilization of, the new MT minus-end\r\ncreated
    by katanin-mediated severing at crossovers. Notably, our findings suggest that\r\ndynamic
    and reversible phosphorylation at S579 of SPR2 is crucial for the proper functioning\r\nof
    the MT severing machinery. Finally, we identify MAP65-1 and CLASP as additional
    targets\r\nof cytokinin-dependent phosphoregulation. Cytokinin treatment decreases
    MT-MAP65-1\r\nassociation in elongating cells, likely to expose MTs to KTN1-mediated
    severing, whereas it\r\nincreases MT-CLASP association to stabilize the growing
    plus-end. In this way, cytokinin drives\r\nMT reorganization during cell development
    by simultaneously modulating several\r\nmicrotubule-associated proteins. These
    results reveal key molecular players in hormonemediated cytoskeletal regulation,
    and highlight protein phosphorylation as a powerful tool\r\nduring this process."
acknowledged_ssus:
- _id: Bio
- _id: LifeSc
acknowledgement: Special thanks to the Plant Facility.
alternative_title:
- ISTA Thesis
article_processing_charge: No
author:
- first_name: Syamala
  full_name: Inumella, Syamala
  id: F8660870-D756-11E9-98C5-34DFE5697425
  last_name: Inumella
  orcid: 0009-0002-5890-120X
citation:
  ama: Inumella S. Molecular mechanisms of microtubule reorganization in elongating
    root epidermal cells. 2025. doi:<a href="https://doi.org/10.15479/AT-ISTA-19722">10.15479/AT-ISTA-19722</a>
  apa: Inumella, S. (2025). <i>Molecular mechanisms of microtubule reorganization
    in elongating root epidermal cells</i>. Institute of Science and Technology Austria.
    <a href="https://doi.org/10.15479/AT-ISTA-19722">https://doi.org/10.15479/AT-ISTA-19722</a>
  chicago: Inumella, Syamala. “Molecular Mechanisms of Microtubule Reorganization
    in Elongating Root Epidermal Cells.” Institute of Science and Technology Austria,
    2025. <a href="https://doi.org/10.15479/AT-ISTA-19722">https://doi.org/10.15479/AT-ISTA-19722</a>.
  ieee: S. Inumella, “Molecular mechanisms of microtubule reorganization in elongating
    root epidermal cells,” Institute of Science and Technology Austria, 2025.
  ista: Inumella S. 2025. Molecular mechanisms of microtubule reorganization in elongating
    root epidermal cells. Institute of Science and Technology Austria.
  mla: Inumella, Syamala. <i>Molecular Mechanisms of Microtubule Reorganization in
    Elongating Root Epidermal Cells</i>. Institute of Science and Technology Austria,
    2025, doi:<a href="https://doi.org/10.15479/AT-ISTA-19722">10.15479/AT-ISTA-19722</a>.
  short: S. Inumella, Molecular Mechanisms of Microtubule Reorganization in Elongating
    Root Epidermal Cells, Institute of Science and Technology Austria, 2025.
corr_author: '1'
date_created: 2025-05-23T15:21:29Z
date_published: 2025-05-23T00:00:00Z
date_updated: 2026-06-12T08:34:29Z
day: '23'
ddc:
- '580'
degree_awarded: PhD
department:
- _id: GradSch
- _id: EvBe
doi: 10.15479/AT-ISTA-19722
file:
- access_level: open_access
  checksum: 847ec70b2e40f50e0ddc7b8da201d52c
  content_type: application/pdf
  creator: sinumell
  date_created: 2025-05-28T11:59:11Z
  date_updated: 2026-05-23T22:30:02Z
  embargo: 2026-05-23
  file_id: '19757'
  file_name: Final Thesis_Syamala Inumella.pdf
  file_size: 8292363
  relation: main_file
- access_level: closed
  checksum: 17cdffdae13a5f65bdad9c84e9e0e3bd
  content_type: application/vnd.openxmlformats-officedocument.wordprocessingml.document
  creator: sinumell
  date_created: 2025-05-28T11:59:11Z
  date_updated: 2026-05-23T22:30:02Z
  embargo_to: open_access
  file_id: '19758'
  file_name: Final Thesis_Syamala Inumella.docx
  file_size: 7145703
  relation: source_file
file_date_updated: 2026-05-23T22:30:02Z
has_accepted_license: '1'
language:
- iso: eng
month: '05'
oa: 1
oa_version: Published Version
page: '113'
publication_identifier:
  isbn:
  - 978-3-99078-059-6
  issn:
  - 2663-337X
publication_status: published
publisher: Institute of Science and Technology Austria
status: public
supervisor:
- first_name: Eva
  full_name: Benková, Eva
  id: 38F4F166-F248-11E8-B48F-1D18A9856A87
  last_name: Benková
  orcid: 0000-0002-8510-9739
title: Molecular mechanisms of microtubule reorganization in elongating root epidermal
  cells
type: dissertation
user_id: 8b945eb4-e2f2-11eb-945a-df72226e66a9
year: '2025'
...