NBS-LRR genes of Musa acuminata is involved in disease resistance to Fusarium wilt

Nucleotide binding site-leucine-rich repeat (NBS-LRR) genes are the most abundant known plant resistance (R) genes and are essential for plant stress tolerance. Fusarium oxysporum f. sp. cubense (Foc) is the causal agent of Banana Fusarium vascular wilt that threatens global banana production, yet, the role of NBS-LRR in disease resistance is unknown. We performed a genome-wide identification and analysis of NBS-LRR genes in M. acuminata and revealed a total of 97 NBS-LRR genes, of which 71 were divided into 17 clusters. Analyses of phylogenetic and conserved motifs indicated that NBS-LRR genes in the same cluster were conserved. Transcriptomic analysis revealed divergent functions of the NBS-LRR genes; genes within cluster 17 were activated in a moderately disease-resistant cultivar but repressed in a susceptible cultivar, especially the MaNBS89 gene. Transcriptional silencing of MaNBS89 led to more serious leaf injury compared to control plants. Overall, our study comprehensively revealed the expression profiles of NBS-LRR genes in an economically important plant and suggested a strong candidate gene (MaNBS89) for future use in resistance breeding in Musa diseases.