Brown algae (Phaeophyceae) are complex photosynthetic organisms with a very different evolutionary history to green plants, to which they are only distantly related1. These seaweeds are the dominant species in rocky coastal ecosystems and they exhibit many interesting adaptations to these, often harsh, environments. Brown algae are also one of only a small number of eukaryotic lineages that have evolved complex multicellularity (Fig. 1). We report the 214 million base pair (Mbp) genome sequence of the filamentous seaweed Ectocarpus siliculosus (Dillwyn) Lyngbye, a model organism for brown algae2, 3, 4, 5, closely related to the kelps6, 7 (Fig. 1). Genome features such as the presence of an extended set of light-harvesting and pigment biosynthesis genes and new metabolic processes such as halide metabolism help explain the ability of this organism to cope with the highly variable tidal environment. The evolution of multicellularity in this lineage is correlated with the presence of a rich array of signal transduction genes. Of particular interest is the presence of a family of receptor kinases, as the independent evolution of related molecules has been linked with the emergence of multicellularity in both the animal and green plant lineages. The Ectocarpus genome sequence represents an important step towards developing this organism as a model species, providing the possibility to combine genomic and genetic2 approaches to explore these and other4, 5 aspects of brown algal biology further.
At a glance
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- Supplementary Information (1.4M)
This file contains Supplementary Methods (1.1-1.21), Supplementary Notes comprising: Genome Structure and organization (2.1-2.18); Metabolism (2.2.1-2.2.13); Signalling and cell biology (2.3.1-2.3.16) and References.
- Supplementary Figures (9.1M)
This file contains Supplementary Figures 1-55 with legends.
- Supplementary Tables (1.1M)
This file contains Supplementary Tables 1-42.