Genomic Clues to the Ancestral Flowering Plant

摘要

Amborella trichopoda is an under-story shrub that is endemic to New Caledonia (see the figure). It is an early-diverging flowering plant-most phy-logenetic studies indicate that it diverged from the lineage leading to most flowering plants, and it is the single sister species to all other extant angiosperms (1). As such, it represents the equivalent of the duck-billed platypus in mammals (in the earliest branch of the mammalian family tree). Given its pivotal position in flowering plant phylog-eny, it has been of considerable interest to sequence its genome. On page 1467 of this issue, the Amborella Genome Project (2) reports the nuclear genome sequence, with extensive analyses. In addition, on page 1468, Rice et al.