Chimeric origins of ochrophytes and haptophytes revealed through an ancient plastid proteome
- École Normale Supérieure, CNRS, Inserm, PSL Research University, France
- Arizona State University, United States
- Université Pierre et Marie Curie, France
- University of Alberta, Canada
- CNRS, UPMC, FR2424, ABiMS, Station Biologique, France
- Sorbonne Universités, UPMC Univ Paris 06, CNRS UMR 7144, France
Abstract
Plastids are supported by a wide range of proteins encoded within the nucleus and imported from the cytoplasm. These plastid-targeted proteins may originate from the endosymbiont, the host, or other sources entirely. Here, we identify and characterise 770 plastid-targeted proteins that are conserved across the ochrophytes, a major group of algae including diatoms, pelagophytes and kelps, that possess plastids derived from red algae. We show that the ancestral ochrophyte plastid proteome was an evolutionary chimera, with 25% of its phylogenetically tractable proteins deriving from green algae. We additionally show that functional mixing of host and plastid proteomes, such as through dual targeting, is an ancestral feature of plastid evolution. Finally, we detect a clear phylogenetic signal from one ochrophyte subgroup, the lineage containing pelagophytes and dictyochophytes, in plastid-targeted proteins from another major algal lineage, the haptophytes. This may represent a possible serial endosymbiosis event deep in eukaryotic evolutionary history.
Data availability
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Research data supporting 'The ancestral ochrophyte plastid proteome'Publicly available at Apollo (https://www.repository.cam.ac.uk/).
Article and author information
Author details
Funding
EMBO (ALTF 1124/2014)
- Richard G Dorrell
ERC (Diatomite)
- Chris Bowler
LouisD Foundation
- Chris Bowler
FP7 (615274)
- Eric P Bapteste
Gordon and Betty Moore Foundation
- Chris Bowler
MEMO-LIFE (ANR- 10-LABX-54)
- Chris Bowler
ANR (ANR-11-IDEX-0001-02)
- Chris Bowler
ANR (ANR-11-BTBR-0008)
- Daniel J Richter
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2017, Dorrell 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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Chimeric origins of ochrophytes and haptophytes revealed through an ancient plastid proteome
eLife 6:e23717.
https://doi.org/10.7554/eLife.23717
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