Last month, the B. oleracea research team reported a draft of genome sequence of B. oleracea, comparing it with those of its sister species to reveal multi-layer asymmetrical evolution of Brassica genomes. The research findings were published in the latest issue of Nation-Communications.
The genusBrassica comprises many important crops, including B. rapa(AA) and B. oleracea (CC), common vegetable crops in China, and their hybrid species B. napus (AACC), a major oil crop in China. The completion of B. oleracea genome sequencingis another important step after the full genome sequencing of B.rapa in the genetic study of the genus Brassica.
As the leading scientist of the Brassica oleracea project, Liu Shengyi fromthe Oilcrops Research Institute said that the research predicts a total of 45,758 protein-coding genes for B. oleracea. As most of B. oleracea genomes are in lineage with Arabidopsis thaliana genomes, B. oleracea serves a model for the study of polyploid genome evolution. So far, the project revealednumerous chromosome rearrangements and asymmetrical gene loss in duplicated genomic blocks, asymmetrical amplification of transposable elements, differential gene co-retention for specific pathways and variation in gene expression, including alternative splicing, among a large number of paralogous and orthologous genes. These data provide insights into the dynamics of Brassica genome evolution and divergence, and serve as important resources for vegetable and oilseed crop breeding in the genus Brassica.
Another important finding of theBrassica oleracea genetics project is that B. oleracea crops have potent anti-cancer properties. Researches in the past already proved that eating crops of the family Brassicaceae have the effects of preventing and controlling cancer, and this time, the research results indicate that B. oleracea crops may have the highest anticancer value in thefamily Brassicaceae.
According to Mr. Wang Hanzhong, leader of the B. napus and B. oleracea genome sequencing team under the Multinational Brassica Genome Project, genomic study of the genus Brassica is of fundamental importance, and will provide guidance to genetic improvement of B. napus and the foundation for molecular breeding of B. napus.