Somayeh Babashpour - Department of Biotechnology, College of Agriculture, Bu-Ali Sina University, Hamadan, Iran
Khosro Piri - Department of Biotechnology, College of Agriculture, Bu-Ali Sina University, Hamadan, Iran
Haidar Saify Nabiabad - Department of Medicinal Plant Production, Nahavand University, Nahavand, Iran
Farzaneh Sabouni - Department of Molecular Medicine, National Institute of Genetic Engineering and Biotechnology, Tehran, Iran

Dopamine is one of the important medications of Portulaca oleracea L. To optimize the production of dopamine, one of the methods is the identification and engineering of metabolite pathways. To investigate the tyrosine decarboxylase (TDC) and tyrosinase, which seem to be the most important genes in dopamine synthesis pathway, hairy roots were produced from Portulaca oleracea using Agrobacterium rhizogenes and total RNA was extracted from hairy roots. A cDNA library was synthesized using RT-PCR. Then, the twogenes were amplified, isolated and cloned in a pTG ۱۹-T vector. Bioinformatics' databases were used to predict the details of the structural, functional and biological characteristic of these genes. Nucleotide sequence analysis revealed that the cloned cDNAs expressed TDC and tyrosinase, and contained a single open reading frame of ۱۸۰۰ bp and ۱۷۵۰ bp, respectively. TDC has the most similarity with TDC of Arabidopsis thaliana (L.) Heynh.,but tyrosinase has ۹۸% similarity withtyrosinase of Agaricus bisporus. Because of More negatively charged amino acids the TDC has hydrophobic properties, therefore affinity and hydrophilic chromatography can be used for purification of TDC. But tyrosinase has hydrophilic properties and hydrophobicity chromatography can be used for its purification. There were two peroxisomal signal peptide (KLAKEFEQL) and (KIEGRPLHL) in the TDC and tyrosinase, respectively. Therefore, they are biologically active in the peroxisomes, and included in biosynthesis dopamine through the transformation of L-lysine to L-dopa and finally to the dopamine. In conclusion, increasing the expression of TDC and tyrosinase through the genetic engineering can increase dopamine production in the Portolaca.

Cloning, Portulaca oleracea, Sequence analysis, Tyrosinase, Tyrosine decarboxylase