Genome-wide identification of PDX and expression analysis under waterlogging stress exhibit stronger waterlogging tolerance in transgenic Brassica napus plants overexpressing the BnaPDX1.3 gene compared to wild-type plants

The <i>PDX</i> gene is a key gene in the vitamin B6 synthesis pathway, playing a crucial role in plant growth, development, and stress tolerance. To explore the family characteristics of the <i>PDX</i> gene in <i>Brassica napus</i> (<i>B. napus</i>) and its regulatory function under waterlogging stress, this study used five <i>PDX</i> genes from Arabidopsis thaliana as the basis for sequence analysis. Thirteen, eight, and six <i>PDX</i> genes were identified in <i>B. napus</i>, <i>Brassica oleracea</i> (<i>B. oleracea</i>), and <i>Brassica rapa</i> (<i>B. rapa</i>), respectively. Bioinformatics study reveals high conservation of <i>PDX</i> subfamily genes during evolution, and <i>PDX</i> genes in <i>B. napus</i> respond to waterlogging stress.In order to further investigate the effect of the <i>PDX</i> gene on waterlogging tolerance in <i>B. napus</i>, expression analysis was conducted on <i>BnaPDX1.3</i> gene overexpressing <i>B. napus</i> plants and wild-type plants. The study showed that overexpressing plants could synthesize more VB6 under waterlogging stress, exhibit stronger antioxidant enzyme activity, and have a more effective and stable ROS scavenging system, thus exhibiting a healthier phenotype. These findings suggested that the <i>BnaPDX1.3</i> gene can enhance the waterlogging tolerance of <i>B. napus</i>, which is of great significance for its response to waterlogging stress. Our study provides a basic reference for further research on the regulation mechanism of the <i>PDX</i> gene and waterlogging tolerance in <i>B. napus</i>.