Chimeric origins of ochrophytes and haptophytes revealed through an ancient plastid proteome

Richard G. Dorrell, Gillian Gile, Giselle McCallum, Raphaël Méheust, Eric P. Bapteste, Christen M. Klinger, Loraine Brillet-Guéguen, Katalina D. Freeman, Daniel J. Richter, Chris Bowler

Research output: Contribution to journalArticlepeer-review

86 Scopus citations


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 nucleus-encoded 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.

Original languageEnglish (US)
Article numbere23717
StatePublished - May 12 2017

ASJC Scopus subject areas

  • Neuroscience(all)
  • Biochemistry, Genetics and Molecular Biology(all)
  • Immunology and Microbiology(all)


Dive into the research topics of 'Chimeric origins of ochrophytes and haptophytes revealed through an ancient plastid proteome'. Together they form a unique fingerprint.

Cite this