Genome sequencing of the high oil crop sesame provides insight into oil biosynthesis
- Equal contributors
1 Oil Crops Research Institute of the Chinese Academy of Agricultural Sciences, Key Laboratory of Biology and Genetic Improvement of Oil Crops of the Ministry of Agriculture, Wuhan 430062, China
2 Beijing Genomics Institute (BGI) - Shenzhen, Shenzhen 518083, China
3 Department of Biology, University of Copenhagen, Copenhagen DK-2200, Denmark
4 Yanzhuang Oil Co., Ltd, Hefei 231283, China
5 International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), Patancheru 502324, India
6 CGIAR Generation Challenge Programme (GCP), c/o CIMMYT, Mexico DF 6-641 06600, Mexico
Genome Biology 2014, 15:R39 doi:10.1186/gb-2014-15-2-r39Published: 27 February 2014
Sesame, Sesamum indicum L., is considered the queen of oilseeds for its high oil content and quality, and is grown widely in tropical and subtropical areas as an important source of oil and protein. However, the molecular biology of sesame is largely unexplored.
Here, we report a high-quality genome sequence of sesame assembled de novo with a contig N50 of 52.2 kb and a scaffold N50 of 2.1 Mb, containing an estimated 27,148 genes. The results reveal novel, independent whole genome duplication and the absence of the Toll/interleukin-1 receptor domain in resistance genes. Candidate genes and oil biosynthetic pathways contributing to high oil content were discovered by comparative genomic and transcriptomic analyses. These revealed the expansion of type 1 lipid transfer genes by tandem duplication, the contraction of lipid degradation genes, and the differential expression of essential genes in the triacylglycerol biosynthesis pathway, particularly in the early stage of seed development. Resequencing data in 29 sesame accessions from 12 countries suggested that the high genetic diversity of lipid-related genes might be associated with the wide variation in oil content. Additionally, the results shed light on the pivotal stage of seed development, oil accumulation and potential key genes for sesamin production, an important pharmacological constituent of sesame.
As an important species from the order Lamiales and a high oil crop, the sesame genome will facilitate future research on the evolution of eudicots, as well as the study of lipid biosynthesis and potential genetic improvement of sesame.