Abstract
BACKGROUND: Manganese (Mn), a heavy metal, induces oxidative stress when present in excess, thereby inhibiting plant growth. The Delay of Germination 1 (DOG1) gene family plays a crucial role in seed dormancy and germination. However, the genome-wide organization and functional roles of the DOG1 gene family under Mn stress remain uncharacterized in Brassica napus. RESULTS: In this study, we identified 42 BnDOG1 family members and elucidated their regulatory roles under Mn stress using whole-genome and differential transcriptomic analyses. The BnDOG1 genes were evenly distributed across 16 chromosome scaffolds, and all members contained the conserved DOG1 domain. Phylogenetic analysis classified the BnDOG1 genes into five subfamilies. Covariance analysis indicated that segmental duplication was the primary mechanism driving gene expansion. Gene Ontology (GO) enrichment analysis revealed the highest enrichment in biological process categories. Notably, BnDOG1 genes were induced by Mn stress. CONCLUSIONS: In this study, we demonstrate that the BnDOG1 gene plays a critical role in mediating physiological responses to environmental stress, thereby establishing a foundation for the development of heavy metal–tolerant crops. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12870-026-08296-1.