Molecular analysis of the sex chromosomes of the platyfish Xiphophorus maculatus: Towards the identification of a new type of master sexual regulator in vertebrates

Research output: Contribution to journalResearch articleContributedpeer-review

Contributors

  • Astrid Böhne - (Author)
  • Christina Schultheis - (Author)
  • Delphine Galiana-Arnoux - (Author)
  • Alexander Froschauer - , University of Würzburg (Author)
  • Qingchun Zhou - (Author)
  • Cornelia Schmidt - (Author)
  • Yvonne Selz - (Author)
  • Catherine Ozouf-Costaz - (Author)
  • Agnès Dettai - (Author)
  • Béatrice Segurens - (Author)
  • Arnaud Couloux - (Author)
  • Sylvie Bernard-Samain - (Author)
  • Valérie Barbe - (Author)
  • Stefan Chilmonczyk - (Author)
  • Frédéric Brunet - (Author)
  • Amandine Darras - (Author)
  • Marta Tomaszkiewicz - (Author)
  • Marie Semon - (Author)
  • Manfred Schartl - (Author)
  • Jean-Nicolas Volff - (Author)

Abstract

In contrast to mammals and birds, fish display an amazing diversity of genetic sex determination systems, with frequent changes during evolution possibly associated with the emergence of new sex chromosomes and sex-determining genes. To better understand the molecular and evolutionary mechanisms driving this diversity, several fish models are studied in parallel. Besides the medaka (Oryzias latipes Temminck and Schlegel, 1846) for which the master sex-determination gene has been identified, one of the most advanced models for studying sex determination is the Southern platyfish (Xiphophorus maculatus, Günther 1966). Xiphophorus maculatus belongs to the Poeciliids, a family of live-bearing freshwater fish, including platyfish, swordtails and guppies that perfectly illustrates the diversity of genetic sex-determination mechanisms observed in teleosts. For X. maculatus, bacterial artificial chromosome contigs covering the sex-determination region of the X and Y sex chromosomes have been constructed. Initial molecular analysis demonstrated that the sex-determination region is very unstable and frequently undergoes duplications, deletions, inversions and other rearrangements. Eleven gene candidates linked to the master sex-determining gene have been identified, some of them corresponding to pseudogenes. All putative genes are present on both the X and the Y chromosomes, suggesting a poor degree of differentiation and a young evolutionary age for platyfish sex chromosomes. When compared with other fish and tetrapod genomes, syntenies were detected only with autosomes. This observation supports an independent origin of sex chromosomes, not only in different vertebrate lineages but also between different fish species.

Details

Original languageEnglish
Pages (from-to)277-284
Number of pages8
JournalIntegrative zoology
Volume4
Issue number3
Publication statusPublished - Sept 2009
Peer-reviewedYes
Externally publishedYes

External IDs

Scopus 79960065550
ORCID /0000-0001-9326-7967/work/142252301

Keywords

Keywords

  • Animals, Chromosomes, Artificial, Bacterial, Cyprinodontiformes/genetics, Evolution, Molecular, Sex Chromosomes/genetics, Sex Determination Processes/genetics, Synteny/genetics

Library keywords