---
_id: '9623'
abstract:
- lang: eng
  text: "Cytoplasmic reorganizations are essential for morphogenesis. In large cells
    like oocytes, these reorganizations become crucial in patterning the oocyte for
    later stages of embryonic development. Ascidians oocytes reorganize their cytoplasm
    (ooplasm) in a spectacular manner. Ooplasmic reorganization is initiated at fertilization
    with the contraction of the actomyosin cortex along the animal-vegetal axis of
    the oocyte, driving the accumulation of cortical endoplasmic reticulum (cER),
    maternal mRNAs associated to it and a mitochondria-rich subcortical layer – the
    myoplasm – in a region of the vegetal pole termed contraction pole (CP). Here
    we have used the species Phallusia mammillata to investigate the changes in cell
    shape that accompany these reorganizations and the mechanochemical mechanisms
    underlining CP formation.\r\nWe report that the length of the animal-vegetal (AV)
    axis oscillates upon fertilization: it first undergoes a cycle of fast elongation-lengthening
    followed by a slow expansion of mainly the vegetal pole (VP) of the cell. We show
    that the fast oscillation corresponds to a dynamic polarization of the actin cortex
    as a result of a fertilization-induced increase in cortical tension in the oocyte
    that triggers a rupture of the cortex at the animal pole and the establishment
    of vegetal-directed cortical flows. These flows are responsible for the vegetal
    accumulation of actin causing the VP to flatten. \r\nWe find that the slow expansion
    of the VP, leading to CP formation, correlates with a relaxation of the vegetal
    cortex and that the myoplasm plays a role in the expansion. We show that the myoplasm
    is a solid-like layer that buckles under compression forces arising from the contracting
    actin cortex at the VP. Straightening of the myoplasm when actin flows stops,
    facilitates the expansion of the VP and the CP. Altogether, our results present
    a previously unrecognized role for the myoplasm in ascidian ooplasmic segregation.
    \r\n"
acknowledged_ssus:
- _id: Bio
- _id: EM-Fac
- _id: NanoFab
- _id: M-Shop
alternative_title:
- ISTA Thesis
article_processing_charge: No
author:
- first_name: Silvia
  full_name: Caballero Mancebo, Silvia
  id: 2F1E1758-F248-11E8-B48F-1D18A9856A87
  last_name: Caballero Mancebo
  orcid: 0000-0002-5223-3346
citation:
  ama: Caballero Mancebo S. Fertilization-induced deformations are controlled by the
    actin cortex and a mitochondria-rich subcortical layer in ascidian oocytes. 2021.
    doi:<a href="https://doi.org/10.15479/at:ista:9623">10.15479/at:ista:9623</a>
  apa: Caballero Mancebo, S. (2021). <i>Fertilization-induced deformations are controlled
    by the actin cortex and a mitochondria-rich subcortical layer in ascidian oocytes</i>.
    Institute of Science and Technology Austria. <a href="https://doi.org/10.15479/at:ista:9623">https://doi.org/10.15479/at:ista:9623</a>
  chicago: Caballero Mancebo, Silvia. “Fertilization-Induced Deformations Are Controlled
    by the Actin Cortex and a Mitochondria-Rich Subcortical Layer in Ascidian Oocytes.”
    Institute of Science and Technology Austria, 2021. <a href="https://doi.org/10.15479/at:ista:9623">https://doi.org/10.15479/at:ista:9623</a>.
  ieee: S. Caballero Mancebo, “Fertilization-induced deformations are controlled by
    the actin cortex and a mitochondria-rich subcortical layer in ascidian oocytes,”
    Institute of Science and Technology Austria, 2021.
  ista: Caballero Mancebo S. 2021. Fertilization-induced deformations are controlled
    by the actin cortex and a mitochondria-rich subcortical layer in ascidian oocytes.
    Institute of Science and Technology Austria.
  mla: Caballero Mancebo, Silvia. <i>Fertilization-Induced Deformations Are Controlled
    by the Actin Cortex and a Mitochondria-Rich Subcortical Layer in Ascidian Oocytes</i>.
    Institute of Science and Technology Austria, 2021, doi:<a href="https://doi.org/10.15479/at:ista:9623">10.15479/at:ista:9623</a>.
  short: S. Caballero Mancebo, Fertilization-Induced Deformations Are Controlled by
    the Actin Cortex and a Mitochondria-Rich Subcortical Layer in Ascidian Oocytes,
    Institute of Science and Technology Austria, 2021.
date_created: 2021-07-01T14:50:17Z
date_published: 2021-07-01T00:00:00Z
date_updated: 2023-09-07T13:33:27Z
ddc:
- '570'
degree_awarded: PhD
department:
- _id: GradSch
- _id: CaHe
doi: 10.15479/at:ista:9623
file:
- access_level: closed
  checksum: e039225a47ef32666d59bf35ddd30ecf
  content_type: application/vnd.openxmlformats-officedocument.wordprocessingml.document
  creator: scaballe
  date_created: 2021-07-01T14:48:54Z
  date_updated: 2022-07-02T22:30:06Z
  embargo_to: open_access
  file_id: '9624'
  file_name: PhDThesis_SCM.docx
  file_size: 131946790
  relation: source_file
- access_level: open_access
  checksum: dd4d78962ea94ad95e97ca7d9af08f4b
  content_type: application/pdf
  creator: scaballe
  date_created: 2021-07-01T14:46:25Z
  date_updated: 2022-07-02T22:30:06Z
  embargo: 2022-07-01
  file_id: '9625'
  file_name: PhDThesis_SCM.pdf
  file_size: 17094958
  relation: main_file
file_date_updated: 2022-07-02T22:30:06Z
has_accepted_license: '1'
language:
- iso: eng
month: '07'
oa: 1
oa_version: Published Version
page: '111'
publication_identifier:
  isbn:
  - 978-3-99078-012-1
  issn:
  - 2663-337X
publication_status: published
publisher: Institute of Science and Technology Austria
related_material:
  record:
  - id: '9750'
    relation: part_of_dissertation
    status: public
  - id: '9006'
    relation: part_of_dissertation
    status: public
status: public
supervisor:
- first_name: Carl-Philipp J
  full_name: Heisenberg, Carl-Philipp J
  id: 39427864-F248-11E8-B48F-1D18A9856A87
  last_name: Heisenberg
  orcid: 0000-0002-0912-4566
title: Fertilization-induced deformations are controlled by the actin cortex and a
  mitochondria-rich subcortical layer in ascidian oocytes
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: c635000d-4b10-11ee-a964-aac5a93f6ac1
year: '2021'
...