Genome-wide identification and characterization of the Brassinazole-resistant gene family and associated responses to osmotic stress in Avena sativa

In this study, we mapped 14 members of the <i>BZR</i> gene family across 12 oat chromosomes, and classified them into three groups based on phylogenetic analysis. The BZR proteins displayed group-specific patterns in their exon-intron structures and conserved motifs. Furthermore, cis-acting element analysis revealed that <i>AsBZR</i> genes are primarily involved in phytohormone responses and environmental stress adaptation. Examination of gene duplication revealed that segmental duplications drove the expansion of the <i>BZR</i> gene family in the oat genome, with evidence of strong purifying selection pressure during evolutionary development. The qRT-PCR analysis demonstrated varied expression patterns among <i>AsBZR</i> members. Specifically, <i>AsBZR12</i> was significantly upregulated in roots, stems, and leaves, with nuclear localization. In summary, our study provides a comprehensive analysis of the <i>AsBZR</i> genes and characterizes their expression patterns under osmotic stress conditions, thereby identifying potential candidate genes for future research. This research provides comprehensive insights into <i>BZR</i> gene structure and evolution, establishing a foundation for understanding their osmotic stress responses in oat.