A Golden2-like transcription factor regulates Brassica napus seed vigor after artificial aging

A novel GLK transcription factor, BnaA03.G2-like, regulates seed vigor after aging by affecting FAs composition in B. napus. Seeds, a most crucial materials for crop production, constitute the basis of agriculture. Seed aging usually occurs during storage, especially for seeds with high oil content. However, the genes and mechanisms underlying seed aging in Brassica napus, a widely grown oilseed crop, remain largely unexplored. In this study, nine SNPs associated with seed vigor after aging were identified through a genome-wide association study, and transgenic seeds confirmed that BnaA03.G2-like negatively regulated seed vigor after aging. Haplotype and gene-based association analyses revealed that S_A3.16900957 and S_A3.16901008 were two core variants located within BnaA03.G2-like. Transcriptome analysis and gas chromatography results suggested that BnaA03.G2-like regulated fatty acid biosynthesis, and the linoleic acid content significantly increased in the seeds of BnaA03.G2-like overexpression lines but decreased in the seeds of BnaA03.G2-like RNA interference lines. Further correlation analysis and malondialdehyde determination revealed that BnaA03.G2-like regulated seed vigor by affecting the linoleic acid content in mature seeds and the degree of membrane lipid peroxidation during seed aging. This study initially reported the function of BnaA03.G2-like and its favorable alleles, providing genetic resources for seed antiaging breeding in B. napus.