Analysis of banana fruit-specific promoters using transient expression in embryogenic cells of banana cultivar Robusta (AAA Group)

The study reports the transient expression of gusA gene in embryogenic cells using three banana derived fruit-specific promoters. Banana embryogenic cells were transformed with a pCAMBIA-1301 derived plasmid construct harboring gusA gene driven by either chitinase, glucanase or expansin promoters derived from banana. The transient expression of ??-glucuronidase was studied 5?days after co-cultivation with Agrobacterium harboring the expression plasmids. The transformed embryogenic cells were treated with different inducers of ethylene such as ethephon, methyl jasmonate, methyl salicylate, abscisic acid and indole acetic acid. The maximum expression of 64099.78?pmoles 4-MU/h/mg total protein was noted with expansin promoter when the cells were treated with the combination of ethephon (0.25?mM) and MJ (10?mM). The results suggest that these promoters can be used to achieve fruit-specific expression of useful transgenes in banana. The results should prove to be an important guide for short term expression studies for promoter validation and gene screening.