Genome sequence of foxtail millet (Setaria italica) provides insights into grass evolution and biofuel potential

TLDR

Foxtail millet is a key C4 grass crop in arid regions and serves as a model for other biofuel species such as switchgrass and pearl millet. The authors assembled a 423‑Mb draft genome anchored to nine chromosomes and annotated 38,801 genes. Comparative genomics revealed multiple post‑divergence chromosome fusions with rice and sorghum and identified rearrangements in the C4 photosynthetic pathway.

Abstract

Foxtail millet (Setaria italica), a member of the Poaceae grass family, is an important food and fodder crop in arid regions and has potential for use as a C(4) biofuel. It is a model system for other biofuel grasses, including switchgrass and pearl millet. We produced a draft genome (∼423 Mb) anchored onto nine chromosomes and annotated 38,801 genes. Key chromosome reshuffling events were detected through collinearity identification between foxtail millet, rice and sorghum including two reshuffling events fusing rice chromosomes 7 and 9, 3 and 10 to foxtail millet chromosomes 2 and 9, respectively, that occurred after the divergence of foxtail millet and rice, and a single reshuffling event fusing rice chromosome 5 and 12 to foxtail millet chromosome 3 that occurred after the divergence of millet and sorghum. Rearrangements in the C(4) photosynthesis pathway were also identified.