The tiny eukaryote Ostreococcus provides genomic insights into the paradox of plankton speciation

Brian Palenik*, Jane Grimwood, Andrea Aerts, Pierre Rouzé, Asaf Salamov, Nicholas Putnam, Chris Dupont, Richard Jorgensen, Evelyne Derelle, Stephane Rombauts, Kemin Zhou, Robert Otillar, Sabeeha S. Merchant, Sheila Podell, Terry Gaasterland, Carolyn Napoli, Karla Gendler, Andrea Manuell, Vera Tai, Olivier VallonGwenael Piganeau, Séverine Jancek, Marc Heijde, Kamel Jabbari, Chris Bowler, Martin Lohr, Steven Robbens, Gregory Werner, Inna Dubchak, Gregory J. Pazour, Qinghu Ren, Ian Paulsen, Chuck Delwiche, Jeremy Schmutz, Daniel Rokhsar, Yves Van De Peer, Hervé Moreau, Igor V. Grigoriev

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

493 Citations (Scopus)


The smallest known eukaryotes, at ≈1-μm diameter, are Ostreococcus tauri and related species of marine phytoplankton. The genome of Ostreococcus lucimarinus has been completed and compared with that of O. tauri. This comparison reveals surprising differences across orthologous chromosomes in the two species from highly syntenic chromosomes in most cases to chromosomes with almost no similarity. Species divergence in these phytoplankton is occurring through multiple mechanisms acting differently on different chromosomes and likely including acquisition of new genes through horizontal gene transfer. We speculate that this latter process may be involved in altering the cell-surface characteristics of each species. In addition, the genome of O. lucimarinus provides insights into the unique metal metabolism of these organisms, which are predicted to have a large number of selenocysteine-containing proteins. Selenoenzymes are more catalytically active than similar enzymes lacking selenium, and thus the cell may require less of that protein. As reported here, selenoenzymes, novel fusion proteins, and loss of some major protein families including ones associated with chromatin are likely important adaptations for achieving a small cell size.

Original languageEnglish
Pages (from-to)7705-7710
Number of pages6
JournalProceedings of the National Academy of Sciences of the United States of America
Issue number18
Publication statusPublished - 1 May 2007
Externally publishedYes


Dive into the research topics of 'The tiny eukaryote Ostreococcus provides genomic insights into the paradox of plankton speciation'. Together they form a unique fingerprint.

Cite this