Suppression of ACC oxidase expression in tomato using heterologous gene from banana prolongs shelf-life both on vine and post-harvest.

1-Aminocyclopropane-1-carboxylate (ACC) oxidase is the final enzyme in the biosynthesis of plant hormone ethylene which has been identified as a key player in controlling ripening and softening of fleshy fruit. We have used banana ACC oxidase gene in antisense orientation in order to suppress ethylene biosynthesis in transgenic tomato. There was a significant increment by more than 10 days in the shelf-life of the transgenic fruit post red ripe stage. There were no differences in total soluble sugar content and pH. The amount of ethylene produced by transgenic fruit was always lower at every stage of ripening compared to wild type. The activities of cell-wall hydrolases and ACC oxidase were reduced by 40-60% and 30-40% respectively, in the turning and red ripe stages of transgenic fruits. It is concluded that antisense suppression of ACC oxidase in tomato using heterologous gene provides a suitable system for prolonging on-vine and off-vine shelf-life of tomato after red ripe stage of maturity. [ABSTRACT FROM AUTHOR]