Chiang Mai Journal of Science

Pharmaceutical proteins production in plant suspension culture has been of interest due to the ease of manipulation, low cost and low allergenic reaction in humans. In this work, the constitutive double CaMV 35S promoter and the abiotic stress-responsive promoter of the Rd29a locus were compared to produce Green Fluorescent Protein (GFP) used as a model for secreted protein in Arabidopsis thaliana suspension culture. Induction of Rd29a inducible promoter by plant hormone abscisic acid (ABA) was also studied. A signal sequence (SS) of a 33 kDa rice protein was added to the constructs to promote secretion. The secretion of GFP into the extracellular spaces of the transgenic seedling was detected under confocal microscope. The fl uorescence intensity of GFP in the suspension culture was measured by fl uorometry. A temporal maximum expression of GFP was observed from the CaMV 35S promoter on day 18. This model can be used as an example to produce pharmaceutical proteins in suspension culture in the future.