---
OA_embargo: '12'
OA_place: publisher
_id: '19386'
abstract:
- lang: eng
  text: "Crustaceans are a large group of arthropods with a great diversity of species
    and\r\ndifferent types of sex determination systems and reproductive modes (Subramoniam,
    2017).\r\nThis makes them a great model for exploring the evolution of sex chromosomes
    and sexual\r\ndimorphism and investigating the evolutionary mechanisms driving
    and maintaining the\r\ndiversity of reproductive systems. Within this taxon, Brine
    shrimp of the genus Artemia, a\r\nbranchiopod crustacean, are well suited for
    such explorations, as they have both highly\r\ndimorphic traits and closely related
    sexual and asexual species. Although brine shrimp are\r\nknown to have ZW sex
    chromosomes (Bowen, 1963; Parraguez et al., 2009), the sex\r\nchromosomes are
    still not well characterized at the genomic level, the sex-determination gene\r\nis
    unknown, and it is still unclear whether the same sex chromosomes as shared by
    the\r\ndifferent species.\r\nThe first part of this thesis was to characterize
    the Z and W chromosomes in Artemia\r\nusing an array of methods, from generating
    multiple chromosome and contig level genome\r\nassemblies to identifying W-linked
    scaffolds and transcripts in multiple species using k-mer\r\nbased approaches.\r\nThe
    second part tackles the conservation of the cell type specific regulatory pathways\r\nin
    the female reproductive system between Artemia and Drosophila, and the expression
    of the\r\nZ-specific region throughout meiosis using single-nucleus RNA-seq data.
    Our results show\r\nthat germline cells lack dosage compensation, with a subset
    of cells showing evidence of\r\nextreme repression of the Z chromosome.\r\nWith
    multiple sexual species and several asexual lineages of parthenogenetic females\r\nthat
    produce rare males at low frequencies, Brine shrimp present the perfect opportunity
    to\r\nexplore the transition to asexuality and shed light on the prerequisites
    and repercussions of\r\nthe form of modified meiosis maintaining the asexual lineages.
    The last chapter is an\r\ninvestigation of the molecular pathways involved in
    asexual reproduction in Artemia using\r\nnewly generated single nucleus RNAseq
    and WGS data and previously published data. "
acknowledged_ssus:
- _id: ScienComp
acknowledgement: My PhD work was funded by the Austrian science fund (FWF), as part
  of the SFB Meiosis consortium (https://sfbmeiosis.org/, grant ID FWF SFB F88-10).
alternative_title:
- ISTA Thesis
article_processing_charge: No
author:
- first_name: Marwan N
  full_name: Elkrewi, Marwan N
  id: 0B46FACA-A8E1-11E9-9BD3-79D1E5697425
  last_name: Elkrewi
  orcid: 0000-0002-5328-7231
citation:
  ama: Elkrewi MN. Evolution of sex chromosomes, sex determination and asexuality
    in Artemia brine shrimp. 2025. doi:<a href="https://doi.org/10.15479/AT-ISTA-19386">10.15479/AT-ISTA-19386</a>
  apa: Elkrewi, M. N. (2025). <i>Evolution of sex chromosomes, sex determination and
    asexuality in Artemia brine shrimp</i>. Institute of Science and Technology Austria.
    <a href="https://doi.org/10.15479/AT-ISTA-19386">https://doi.org/10.15479/AT-ISTA-19386</a>
  chicago: Elkrewi, Marwan N. “Evolution of Sex Chromosomes, Sex Determination and
    Asexuality in Artemia Brine Shrimp.” Institute of Science and Technology Austria,
    2025. <a href="https://doi.org/10.15479/AT-ISTA-19386">https://doi.org/10.15479/AT-ISTA-19386</a>.
  ieee: M. N. Elkrewi, “Evolution of sex chromosomes, sex determination and asexuality
    in Artemia brine shrimp,” Institute of Science and Technology Austria, 2025.
  ista: Elkrewi MN. 2025. Evolution of sex chromosomes, sex determination and asexuality
    in Artemia brine shrimp. Institute of Science and Technology Austria.
  mla: Elkrewi, Marwan N. <i>Evolution of Sex Chromosomes, Sex Determination and Asexuality
    in Artemia Brine Shrimp</i>. Institute of Science and Technology Austria, 2025,
    doi:<a href="https://doi.org/10.15479/AT-ISTA-19386">10.15479/AT-ISTA-19386</a>.
  short: M.N. Elkrewi, Evolution of Sex Chromosomes, Sex Determination and Asexuality
    in Artemia Brine Shrimp, Institute of Science and Technology Austria, 2025.
corr_author: '1'
date_created: 2025-03-11T12:54:31Z
date_published: 2025-03-14T00:00:00Z
date_updated: 2026-04-16T12:20:41Z
day: '14'
ddc:
- '570'
- '576'
degree_awarded: PhD
department:
- _id: GradSch
- _id: BeVi
doi: 10.15479/AT-ISTA-19386
file:
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  date_created: 2025-03-26T07:06:56Z
  date_updated: 2026-03-26T23:30:03Z
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has_accepted_license: '1'
language:
- iso: eng
month: '03'
oa: 1
oa_version: Published Version
page: '170'
project:
- _id: 34ae1506-11ca-11ed-8bc3-c14f4c474396
  grant_number: F8810
  name: The highjacking of meiosis for asexual reproduction
publication_identifier:
  eissn:
  - 2663-337X
  isbn:
  - '9783990780534'
publication_status: published
publisher: Institute of Science and Technology Austria
related_material:
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status: public
supervisor:
- first_name: Beatriz
  full_name: Vicoso, Beatriz
  id: 49E1C5C6-F248-11E8-B48F-1D18A9856A87
  last_name: Vicoso
  orcid: 0000-0002-4579-8306
title: Evolution of sex chromosomes, sex determination and asexuality in Artemia brine
  shrimp
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: '2025'
...