Characterization of Banana Genes and Their Expression Analysis under Temperature Stress and Mutualistic and Pathogenic Fungal Colonization.

SNAREs (soluble N-ethylmaleimide-sensitive-factor attachment protein receptors) are engines for almost all of the membrane fusion and exocytosis events in organism cells. In this study, we identified 84 genes from banana (). Gene expression analysis revealed that the expression of s varied a lot in different banana organs. By analyzing their expression patterns under low temperature (4 °C), high temperature (45 °C), mutualistic fungus (, Si) and fungal pathogen ( f. sp. Tropical Race 4, TR4) treatments, many were found to be stress responsive. For example, was up-regulate by both low and high temperature stresses; was up-regulated by low temperature but down-regulated by high temperature; and TR4 treatment up-regulated the expression of but down-regulated and . Notably, the upregulation or downregulation effects of TR4 on the expression of some could be alleviated by priorly colonized Si, suggesting that they play roles in the Si-enhanced banana wilt resistance. resistance assays were performed in tobacco leaves transiently overexpressing , and . Results showed that transient overexpression of and suppressed the penetration and spread of both 1 ( Race 1) and TR4 in tobacco leaves, suggesting that they play positive roles in resisting infection. However, the transient overexpression of facilitated infection. Our study can provide a basis for understanding the roles of in the banana responses to temperature stress and mutualistic and pathogenic fungal colonization.