Pseudis tocantins is the only frog species of the hylid genus Pseudis that possesses highly heteromorphic sex chromosomes. Z and W chromosomes of Ps. tocantins differ in size, morphology, position of the nucleolar organizer region (NOR) and the amount and distribution of heterochromatin. A chromosomal inversion and heterochromatin amplification on the W chromosome were previously inferred to be involved in the evolution of this sex chromosome pair. Despite these findings, knowledge related to the molecular composition of the large heterochromatic band of this W chromosome is restricted to the PcP190 satellite DNA, and no data are available regarding the gene content of either the W or the Z chromosome of Ps. tocantins. Here, we sequenced microdissected Z and W chromosomes of this species to further resolve their molecular composition. Comparative genomic analysis suggests that Ps. tocantins sex chromosomes are likely homologous to chromosomes 4 and 10 of Xenopus tropicalis. Analyses of the repetitive DNA landscape in the Z and W assemblies allowed for the identification of several transposable elements and putative satellite DNA sequences. Finally, some transposable elements from the W assembly were found to be highly diverse and divergent from elements found elsewhere in the genome, suggesting a rapid amplification of these elements on the W chromosome.
|Journal||Journal of Evolutionary Biology|
|State||Accepted/In press - 2022|
Bibliographical noteFunding Information:
The authors acknowledge to São Paulo Research Foundation for financial support (FAPESP #2014‐23542‐ 6). KPG is very thankful for student fellowships from the National Council for Scientific and Technological Development (CNPq #140814/2015‐9) and Coordination for the Improvement of Higher Education Personnel (CAPES) (PDSE program #99999.006901/2015‐08). We thank Cíntia P. Targueta, Melissa Keinath and Vladimir Timoshevskiy for technical assistance. We also thank William P. da Costa for helping in the field expedition to collect individuals and Daniela de Melo e Silva and Mariana Pires de Campos Telles for making their laboratory in the Federal University of Goiás available for chromosome preparations of some specimens of . Pseudis tocantins P. tocantins
© 2022 European Society for Evolutionary Biology.
- next generation sequencing
- repetitive DNA
- sex chromosomes
ASJC Scopus subject areas
- Ecology, Evolution, Behavior and Systematics