Location: Plant, Soil and Nutrition ResearchTitle: The Sorghum bicolor genome and the diversification of grasses Author
Submitted to: Nature
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/9/2008
Publication Date: 1/29/2009
Citation: Paterson, A.H., Bowers, J.E., Maher, C.A., Narechania, A., Zhang, L., Ware, D., Messing, J., Rokhsar, D.S. 2009. The Sorghum bicolor genome and the diversification of grasses. Nature. 457:551-556. Interpretive Summary: For numerous agronomic and economical reasons, sorghum (Sorghum bicolor L. Moench) has the potential to be one of the species dedicated to biomass production. Sorghum, a C4 photosynthetic species, is a highly productive biomass crop and very drought tolerant. This works presents the first report on sequencing, assembly and analysis of the genome, including the protein coding and microRNA non-coding genes, as well as the transposon content of Sorghum. The analysis of the genomes suggests that many of the genes found were conserved in other grasses. The sequence and the annotations will provide a framework for future breeding, molecular and evolutionary studies in sorghum as well as other economically important grasses.
Technical Abstract: Sorghum, an African grass related to sugar cane and maize, is grown for food, feed, fiber and fuel. We present an initial analysis of the 730-megabase Sorghum bicolor (L.) Moench genome, placing 98% of genes in their chromosomal context using whole-genome shotgun sequence validated by genetic, physical and syntenic information. Genetic recombination is largely confined to about one-third of the sorghum genome with gene order and density similar to those of rice. Retrotransposon accumulation in recombinationally recalcitrant heterochromatin explains the 75% larger genome size of sorghum compared with rice. Although gene and repetitive DNA distributions have been preserved since palaeopolyploidization 70 million years ago, most duplicated gene sets lost one member before the sorghum–rice divergence. Concerted evolution makes one duplicated chromosomal segment appear to be only a few million years old. About 24% of genes are grass-specific and 7% are sorghum-specific. Recent gene and microRNA duplications may contribute to sorghum's drought tolerance.