Genome-Wide Identification of the Glycosyl Hydrolase Family 1 Genes in Brassica napus L. and Functional Characterization of BnBGLU77

The β-glucosidases (BGLUs) of Glycoside Hydrolase Family 1 (GH1) exhibit essential functions in plant secondary metabolism and stress responses, mediated by their dual catalytic capabilities in hydrolysis and transglycosylation. This study identified 149 BGLU family members within <i>B. napus</i> (<i>Brassica napus</i> L.), which were systematically categorized into 10 distinct subgroups. Subsequent characterization encompassed detailed examination of their motif composition, chromosomal distribution, gene collinearity, selection pressure, and expression profiling. Transient overexpression of <i>BnBGLU77</i> in <i>N. benthamiana</i> (<i>Nicotiana benthamiana</i>), combined with untargeted metabolomics analysis, revealed pronounced modulatory effects on the degradation and accumulation of β-glucosidic compounds, suggesting potential roles of the protein encoded by <i>BnBGLU77</i> in metabolic homeostasis and stress response mechanisms. These experimental results first validated the bidirectional catalytic activity of a BGLU enzyme in <i>B. napus</i>, while simultaneously advancing fundamental understanding of <i>BnBGLU</i> gene functions and providing new insights for developing stress-resistant rapeseed cultivars through targeted genetic improvement.