Genomics: From sea to sea.

Abstract

The genome sequence of the marine flowering plant eelgrass (Zostera marina) sheds light on how marine algae evolved into land plants before moving back to the sea. See Letter p.331 The seagrass Zostera marina, or eelgrass, is widely distributed throughout the Northern Hemisphere. It is therefore of considerable ecological importance but — as with other seagrasses — its coastal habitats are among the world's most threatened ecosystems. Jeanine Olsen and colleagues report the whole-genome sequence of Zostera. Their analyses provide insights into the evolutionary changes associated with the 'back to the sea' reverse evolutionary trajectory that has occurred in this angiosperm lineage, including the loss of the entire repertoire of stomatal genes, and the presence of sulfated cell-wall polysaccharides that are more macro-algal-like than plant-like.