Taxol is one of the most effective anti-cancer drugs in recent years, which commonly is extracted from Taxus. Nowadays it is used as the most dominant anti-cancer agent with different mechanism from other antineoplastic drugs used in treatment of breast, ovarian, skin, lung and gullet cancers. Many efforts have been made for synthesis and semi-synthesis of Taxol, and also its extraction from cell culture, which none of them were efficient. Widespread use of this drug in medicine and limited production from plant sources, study and survey of biosynthesis mechanism and effective factors on increase synthesis Taxol is required. Vast research indicated that cooperation of environmental elicitors and regulatory elements in promoters of Taxol genes biosynthesis pathway have an important role in Taxol synthesis. The aim of this research is to identify and isolate the promoter of Taxadiene Synthase , the key gene in Taxol biosynthesis pathway in T. baccata , and also in silico promoter analysis to identify regulatory elements and transcription factors in this region. In this research walking DNA genome was used for identification and isolation of the promoter; and UTRdb, PlantCARE and PlantPAN software were used for in silico promoter analysis. The Taxadiene Synthase Promoter with 1578bp length was isolated; also some of transcription factors like ERF1, TBP, MYB and regulatory elements were found. Effect of ethylene on ERF1 and ABA in MYB causes increase in Taxol biosynthesis gene expression and eventually increase Taxol synthesis. Results of promoter analysis indicated some of special regulatory elements such as MBS, G-box and P-box that these elements receive environmental stress signals and regulate expression of Taxadiene Synthase gene in different conditions. Results showed that several endogenous and exogenous factors such as hormones, light, cold, heat and salinity induce Taxadiene Synthase gene Promoter and gene expression. It is expected that with getting effective environmental elicitors together to induce Taxadiene Synthase gene expression finally Taxol biosynthesis increase. Keywords: Taxol, Taxadiene Synthase , Promoter analysis
