Functional repertoire convergence of distantly related eukaryotic plankton lineages revealed by genome-resolved metagenomics

Abstract

Marine planktonic eukaryotes play a critical role in global biogeochemical cycles and climate. However, their poor representation in culture collections limits our understanding of the evolutionary history and genomic underpinnings of planktonic ecosystems. Here, we used 280 billion Tara Oceans metagenomic reads from polar, temperate, and tropical sunlit oceans to reconstruct and manually curate more than 700 abundant and widespread eukaryotic environmental genomes ranging from 10 Mbp to 1.3 Gbp. This genomic resource covers a wide range of poorly characterized eukaryotic lineages that complement long-standing contributions from culture collections while better representing plankton in the upper layer of the oceans. We performed the first comprehensive genome-wide functional classification of abundant unicellular eukaryotic plankton, revealing four major groups connecting distantly related lineages. Neither trophic modes of plankton nor its vertical evolutionary history could explain the functional repertoire convergence of major eukaryotic lineages that coexisted within oceanic currents for millions of years. CoverNavigating on the map of plankton genomics with Tara Oceans and anvio: a comprehensive genome-resolved metagenomic survey dedicated to eukaryotic plankton. O_FIG O_LINKSMALLFIG WIDTH=153 HEIGHT=200 SRC="FIGDIR/small/341214v2_ufig1.gif" ALT="Figure 1"> View larger version (82K): org.highwire.dtl.DTLVardef@536fe5org.highwire.dtl.DTLVardef@1d72cc9org.highwire.dtl.DTLVardef@1bd5281org.highwire.dtl.DTLVardef@739512_HPS_FORMAT_FIGEXP M_FIG C_FIG