The genomes of polyextremophilic Cyanidiales contain 1% horizontally transferred genes with diverse adaptive functions
- Heinrich Heine University, Germany
- Rutgers University, United States
- Arizona State University, United States
Abstract
The role and extent of horizontal gene transfer (HGT) in eukaryotes are hotly disputed topics that impact our understanding of the origin of metabolic processes and the role of organelles in cellular evolution. We addressed this issue by analyzing 10 novel Cyanidiales genomes and determined that 1% of their gene inventory is HGT-derived. Numerous HGT candidates share a close phylogenetic relationship with prokaryotes that live in similar habitats as the Cyanidiales and encode functions related to polyextremophily. HGT candidates differ from native genes in GC-content, number of splice sites, and gene expression. HGT candidates are more prone to loss, which may explain the absence of a eukaryotic pan-genome. Therefore, the lack of a pan-genome and cumulative effects fail to provide substantive arguments against our hypothesis of recurring HGT followed by differential loss in eukaryotes. The maintenance of 1% HGTs, even under selection for genome reduction, underlines the importance of non-endosymbiosis related foreign gene acquisition.
Data availability
The genomic, chloroplast and mitochondrial sequences of the 10 novel genomes, as well as gene models, ESTs, protein sequences, and gene annotations are available at http://porphyra.rutgers.edu.Raw PacBio RSII reads, and also the genomic, chloroplast and mitochondrial sequences, have been submitted to the NCBI and are retrievable via BioProject ID PRJNA512382.
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Genome sequencing of 10 novel Cyanidiales strainsNCBI Sequence Read Archive, PRJNA512382.
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Red Algal Resources to Promote Integrative Research in Algal GenomicsRutgers University, Red Algal.
Article and author information
Author details
Funding
Deutsche Forschungsgemeinschaft (EXC 1028)
- Andreas P M Weber
Heinrich-Heine-Universität Düsseldorf
- Andreas P M Weber
Deutsche Forschungsgemeinschaft (WE 2231/21-1)
- Andreas P M Weber
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Paul B Rainey, Max Planck Institute for Evolutionary Biology, Germany
Version history
- Received: January 10, 2019
- Accepted: May 30, 2019
- Accepted Manuscript published: May 31, 2019 (version 1)
- Version of Record published: July 15, 2019 (version 2)
Copyright
© 2019, Rossoni 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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The genomes of polyextremophilic Cyanidiales contain 1% horizontally transferred genes with diverse adaptive functions
eLife 8:e45017.
https://doi.org/10.7554/eLife.45017
Further reading
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