Improved transient production of a cellulase enzyme in detached sunflower leaves using plant hormones

A synthetic endoglucanase E1 was transiently expressed in detached whole sunflower leaves using recombinant Agrobacterium tumefaciens. As a means to increase protein accumulation, the effect of plant hormones on E1 production was investigated using six different hormones: methyl jasmonic acid (JA), gibberellin A3 (GA), indole acetic acid (IAA), 2,4-dichlorophenoxyacetic acid (2,4-D), kinetin (CK), and salicylic acid (SA). Among the six hormones, JA was best at boosting E1 concentrations, increasing yields as much as six-fold and the JA treatment was especially effective at an early phase of leaf incubation likely by enhancing T-DNA transfer at an early leaf incubation phase. Finally, co-infiltrating combinations of two different hormones revealed an antagonistic interaction between JA and SA in A. tumefaciens-mediated transient expression.