Chromosoma

, Volume 116, Issue 2, pp 159–173

Comparison of the Z and W sex chromosomal architectures in elegant crested tinamou (Eudromia elegans) and ostrich (Struthio camelus) and the process of sex chromosome differentiation in palaeognathous birds

Authors

  • Yayoi Tsuda
    • Laboratory of Cytogenetics, Division of Bioscience, Graduate School of Environmental Earth ScienceHokkaido University
  • Chizuko Nishida-Umehara
    • Laboratory of Cytogenetics, Division of Bioscience, Graduate School of Environmental Earth ScienceHokkaido University
    • Laboratory of Animal Cytogenetics, Division of Genome Dynamics, Creative Research Initiative “Sousei”Hokkaido University
  • Junko Ishijima
    • Laboratory of Animal Cytogenetics, Division of Genome Dynamics, Creative Research Initiative “Sousei”Hokkaido University
  • Kazuhiko Yamada
    • Laboratory of Animal Cytogenetics, Division of Genome Dynamics, Creative Research Initiative “Sousei”Hokkaido University
    • Chromosome Science Labo Inc.
    • Laboratory of Cytogenetics, Division of Bioscience, Graduate School of Environmental Earth ScienceHokkaido University
    • Laboratory of Animal Cytogenetics, Division of Genome Dynamics, Creative Research Initiative “Sousei”Hokkaido University
Research Article

DOI: 10.1007/s00412-006-0088-y

Cite this article as:
Tsuda, Y., Nishida-Umehara, C., Ishijima, J. et al. Chromosoma (2007) 116: 159. doi:10.1007/s00412-006-0088-y

Abstract

To clarify the process of avian sex chromosome differentiation in palaeognathous birds, we performed molecular and cytogenetic characterization of W chromosome-specific repetitive DNA sequences for elegant crested tinamou (Eudromia elegans, Tinamiformes) and constructed comparative cytogenetic maps of the Z and W chromosomes with nine chicken Z-linked gene homologues for E. elegans and ostrich (Struthio camelus, Struthioniformes). A novel family of W-specific repetitive sequences isolated from E. elegans was found to be composed of guanine- and cytosine-rich 293-bp elements that were tandemly arrayed in the genome as satellite DNA. No nucleotide sequence homologies were found for the Struthioniformes and neognathous birds. The comparative cytogenetic maps of the Z and W chromosomes of E. elegans and S. camelus revealed that there are partial deletions in the proximal regions of the W chromosomes in the two species, and the W chromosome is more differentiated in E. elegans than in S. camelus. These results suggest that a deletion firstly occurred in the proximal region close to the centromere of the acrocentric proto-W chromosome and advanced toward the distal region. In E. elegans, the W-specific repeated sequence elements were amplified site-specifically after deletion of a large part of the W chromosome occurred.

Copyright information

© Springer-Verlag 2007