Overexpression of TYDC2 in medicinal plant opium poppy to increase its medicinal alkaloids contents

morphinan group alkaloids in poppy are synthesized from two L-Tyrosine amino acids by 17 anzymatic stages through several continuous oxidative reactions. The first key enzyme on this path is L-Tyrosine decarboxylase (TYDC). Tyrosine decarboxylase is a common cyclic amino acid in plants which in different plant species, biosynthesis of a large number of primary and secondary metabolites depends on it. For over expression of this gene in opium poppy, a suitable gene construct named pBI121-TK was designed, so that Kozak Enhancer as a gene expression enhancer was added at upstream of TYDC2 gene’s start codon and was coloned in pTZ57R/T plasmid. Then, in GUS location under control of CaMV35S promoter and Nos terminator, it entered T-DNA area of pBI121 binary plasmid. Gene transfer optimization by GUS histochemical assay in agroinfiltrated plants was done by pBI121 plasmid containing GUS gene and eventually the agrobacterium containing pBI121-TK recombinant construct was transferred to six-week long plants according to the optimized condition. Amount of morphinan alkaloids was measured by HPLC device. The obtained results indicate 75.2% increase of morphine, codein and thebaine in recombinant sample relative to the control sample.