The genome of Orychophragmus violaceus provides genomic insights into the evolution of Brassicaceae polyploidization and its distinct traits

• DOI: 10.1016/j.xplc.2022.100431
• Publication Date: 2022-09-07T07:18:51Z
• Authors: Kang Zhang; Yinqing Yang; Xin Zhang; Lingkui Zhang; Yu Fu; Zhongwei Guo; Shumin Chen; Jian Wu; James C. Schnable; Keke Yi; Xiaowu Wang; Feng Cheng
• Keywords: Brassicaceae; Genome size; Lineage (genetic)

Orychophragmus violaceus, referred to as "eryuelan" (February orchid) in China, is an early-flowering ornamental plant. The high oil content and abundance of unsaturated fatty acids O. violaceus seeds make it a potential high-quality oilseed crop. Here, we generated whole-genome assembly for using Nanopore Hi-C sequencing technologies. assembled genome was ∼1.3 Gb size, with 12 pairs chromosomes. Through investigation ancestral evolution, determined that the experienced tetraploidization event from diploid progenitor translocated proto-Calepineae karyotype. Comparisons between reconstructed subgenomes identified indicators subgenome dominance, indicating likely originated via allotetraploidy. phylogenetically close Brassica genus, tetraploidy occurred approximately 8.57 million years ago, time triplication arose intermediate tetraploid lineage. However, independent hexaploidization Brassica, evidenced by results detailed phylogenetic analyses comparisons break fusion points genomic blocks. Moreover, identification multi-copy genes regulating production highlighted contributions both tandem duplication functional innovation violaceus. These findings provide novel insights into polyploidization evolution plant species will promote studies domestication/breeding efforts