Evolution of gene dosage on the Z-chromosome of schistosome parasites
- Institute of Science and Technology Austria, Austria
- University of Perpignan via Domitia, France
- Université Grenoble - Alpes, CEA, France
- Justus-Liebig-Universität, Germany
Abstract
XY systems usually show chromosome-wide compensation of X-linked genes, while in many ZW systems, compensation is restricted to a minority of dosage sensitive genes. Why such differences arose is still unclear. Here, we combine comparative genomics, transcriptomics and proteomics to obtain a complete overview of the evolution of gene dosage on the Z-chromosome of Schistosoma parasites. We compare the Z-chromosome gene content of African (Schistosoma mansoni and S. haematobium) and Asian (S. japonicum) schistosomes, and describe lineage-specific evolutionary strata. We use these to assess gene expression evolution following sex-linkage. The resulting patterns suggest a reduction in expression of Z-linked genes in females, combined with up-regulation of the Z in both sexes, in line with the first step of Ohno's classic model of dosage compensation evolution. Quantitative proteomics suggest that post-transcriptional mechanisms do not play a major role in balancing the expression of Z-linked genes.
Data availability
Sequencing data have been deposited to the NCBI short reads archive (PRJNA432803).Proteomic dosage values as well as final versions of the processed datasets (genomic coverage, expression values, chromosomal assignments) have been deposited into the IST Austria Data Repository (http://dx.doi.org/10.15479/AT:ISTA:109).
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DNA reads of male and female S. japonicumProject number: PRJNA432803.
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Proteomic dosage values as well as final versions of the processed datasets (genomic coverage, expression values, chromosomal assignments)Publicly available via the IST data repository.
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Gene atlasing of digestive and reproductive tissues in Schistosoma mansoniPublicly available at the NCBI Gene Expression Omnibus (accession no: GSE23942).
Article and author information
Author details
Funding
Austrian Science Fund (P28842)
- Beatriz Vicoso
Proteomics France Infrastructure (ANR-10-INBS-08-01)
- Yohann Couté
Labex GRAL (ANR-10-LABX-49-01)
- Yohann Couté
Wellcome Trust (107475/Z/15/Z)
- Thomas Quack
- Christoph Grevelding
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2018, Picard et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Evolution of gene dosage on the Z-chromosome of schistosome parasites
eLife 7:e35684.
https://doi.org/10.7554/eLife.35684
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