The opium poppy genome and morphinan production

Morphinan-based painkillers are derived from opium poppy. We report a draft of the opium poppy genome, with 2.72Gb assembled into 11 chromosomes with contig N50 and scaffold N50 of 1.77Mb and 204Mb, respectively. Synteny analysis suggests a whole genome duplication at approximately 7.8 million years ago (MYA) and ancient segmental or whole genome duplication(s) that occurred before the Papaveraceae-Ranunculaceae divergence 110 MYA. Syntenic blocks representative of phthalideisoquinoline and morphinan components of a benzylisoquinoline alkaloid cluster of 15 genes provides insight into how it evolved. Paralog analysis identified P450 and oxidoreductase genes that combined to form the STORR gene fusion essential for morphinan biosynthesis in opium poppy. Thus gene duplication, rearrangement and fusion events have led to evolution of specialized metabolic products in opium poppy.