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. 2012 Jun 7;279(1736):2246-54.
doi: 10.1098/rspb.2011.2301. Epub 2012 Feb 1.

The evolutionary history of haptophytes and cryptophytes: phylogenomic evidence for separate origins

Fabien Burki  1 , Noriko Okamoto, Jean-François Pombert, Patrick J Keeling
Affiliations

The evolutionary history of haptophytes and cryptophytes: phylogenomic evidence for separate origins

Fabien Burki et al. Proc Biol Sci. .

Abstract

An important missing piece in the puzzle of how plastids spread across the eukaryotic tree of life is a robust evolutionary framework for the host lineages. Four assemblages are known to harbour plastids derived from red algae and, according to the controversial chromalveolate hypothesis, these all share a common ancestry. Phylogenomic analyses have consistently shown that stramenopiles and alveolates are closely related, but haptophytes and cryptophytes remain contentious; they have been proposed to branch together with several heterotrophic groups in the newly erected Hacrobia. Here, we tested this question by producing a large expressed sequence tag dataset for the katablepharid Roombia truncata, one of the last hacrobian lineages for which genome-level data are unavailable, and combined this dataset with the recently completed genome of the cryptophyte Guillardia theta to build an alignment composed of 258 genes. Our analyses strongly support haptophytes as sister to the SAR group, possibly together with telonemids and centrohelids. We also confirmed the common origin of katablepharids and cryptophytes, but these lineages were not related to other hacrobians; instead, they branch with plants. Our study resolves the evolutionary position of haptophytes, an ecologically critical component of the oceans, and proposes a new hypothesis for the origin of cryptophytes.

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Figures

Figure 1.
Figure 1.
Phylogeny inferred with the CAT + Γ4 model, based on the most complete taxa sampling. Support values are indicated for relevant nodes or when not maximal (PP/CAT-BP). No value at a node means support equal to 1.0 PP/100% CAT-BP. Dots mark OTUs with complete genome data available. Numbers after the OTU names are the sequence lengths. Scale bar, substitutions per position.
Figure 2.
Figure 2.
Phylogeny inferred with the CAT + Γ4 model, with telonemids, centrohelids and picobiliphytes removed. Support values are indicated for relevant nodes or when not maximal (PP/CAT-BP). No value at a node means support equal to 1.0 PP/100% CAT-BP. Numbers after the OTU names are the sequence lengths. Scale bar, substitutions per position.
Figure 3.
Figure 3.
Phylogenies inferred with the CAT + Γ4 model, based on the dataset shown in figure 2, but with glaucophytes and either cryptophytes (right) or katablepharids (left) removed. Support values are indicated when not maximal (PP). No value at a node means support equal to 1.0 PP. All branches are drawn to scale, except the branches leading to Ciliates and Foraminifera, which were shortened for practical reasons. Scale bar, substitutions per position.
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References

    1. Gould S. B., Waller R. F., McFadden G. I. 2008. Plastid evolution. Annu. Rev. Plant. Biol. 59, 491–51710.1146/annurev.arplant.59.032607.092915 (doi:10.1146/annurev.arplant.59.032607.092915) - DOI - DOI - PubMed
    1. Keeling P. J. 2004. Diversity and evolutionary history of plastids and their hosts. Am. J. Bot. 91, 1481–149310.3732/ajb.91.10.1481 (doi:10.3732/ajb.91.10.1481) - DOI - DOI - PubMed
    1. Reyes-Prieto A., Weber A. P., Bhattacharya D. 2007. The origin and establishment of the plastid in algae and plants. Annu. Rev. Genet. 41, 147–16810.1146/annurev.genet.41.110306.130134 (doi:10.1146/annurev.genet.41.110306.130134) - DOI - DOI - PubMed
    1. Palmer J. D., Soltis D. E., Chase M. W. 2004. The plant tree of life: an overview and some points of view. Am. J. Bot. 91, 1437–144510.3732/ajb.91.10.1437 (doi:10.3732/ajb.91.10.1437) - DOI - DOI - PubMed
    1. Howe C., Barbrook A., Nisbet R., Lockhart P., Larkum A. W. 2008. The origin of plastids. Proc. R. Soc. B 363, 2675–268510.1098/rstb.2008.0050 (doi:10.1098/rstb.2008.0050) - DOI - DOI - PMC - PubMed

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