Over - expression Effect of Gene Encoding 3-hydroxy-3-Methylglutaryl-CoA Reductase on Production of Taxol in Iranian Hazel (Corylus avellana L.)

Background: Sustainable and commercial production of taxol as an anti cancer drug is a critical point to its clinical application. Nowadays, hazel because of rapid growth and wide range distribution is considered as an alternative source of Taxol. Objective: To increase taxol production the cDNA encoding 3-hydroxy-3-methylglutaryl-CoA reductase (HMGR) from Iranian hazel (GeneBank accession number KF306244, showed by CiHMGR) was isolated and over-expressed in pCAMBIA1304 binary vector. The effect of transient over-expression of HMGR in callus and leaf were evaluated on Taxol production. Methods: The calli was established through the culture of immature cotyledon on Murashige and Skoog basal medium supplemented with 2, 4-D and BA. The first strand cDNA of CiHMGR was synthesized by specific primers. Enzymatic assay of recombinant CiHMGR in E. coli were done by western blott and His-tag affinity techniques. Also production of taxol in transformed callus and leaf were evaluated by HPLC analysis. Results: An Open Reading Frame (ORF) with 1698 bp length and a deduced polypeptide with 566 amino acid residues were amplified. The highest and lowest amount of taxol was 0.016 mg/g.DW and 0.004 mg/gDW in transformed calli and untransformed leaves respectively. Conclusion: Generally the over-expression of HMGR increase the total isoprenoids yield, therefore to have high production of target secondary metabolites (taxol) we need both of network of transformed genes and elicited cell culture.