Genome-wide identification and systematic characterization of MATH family genes and expression analysis of response to abiotic stresses in Brassica napus L
Meprin and TRAF-C homology (MATH) proteins function as adaptor molecules and components of E3 ubiquitin ligase complexes. They link receptor-like kinase signalling to downstream regulatory pathways in plants. MATH proteins coordinate growth, hormone signalling, and responses to abiotic stress by modulating ubiquitin-dependent proteostasis. Despite their importance, however, little is known about the diversity, function, and specific regulatory role of the MATH gene family in Brassica napus . We identified 151 BnMATH family genes distributed across the 19 chromosomes of B. napus using a hidden Markov model-based genome-wide search followed by domain validation. Comparative phylogenetic and structural analyses classified these genes into four conserved clades, revealing that extensive segmental and tandem duplication events had driven the family expansion. Promoter analysis revealed more than 6,000 cis-acting regulatory elements associated with hormone- and stress-responsive gene expression. A total of 44 miRNA families targeting BnMATH genes were identified, among which 10 have been previously validated to be involved in biological processes. Transcriptome profiling combined with qRT-PCR validation revealed pronounced tissue-specific and abiotic-stress-responsive expression patterns. Notably, BnMATH06 , BnMATH92, and BnMATH135 were strongly induced by salt and drought stress, suggesting a potential role in stress adaptation. These findings deepen our understanding of the MATH gene family and provide a robust foundation for future functional genomics research targeting their specific biological roles, particularly in hormone-driven regulation and adaptation to abiotic stress.