Genetic Control Of Resveratrol Biosynthesis In Transgenic Plants

Resveratrol is a phytoalexin(antibiotic) produced naturally by several plants to primarily protect them against fungus. It has been found that this also has a number of beneficial health effects, such as anti-cancer, antiviral, euro-protective, anti-aging, anti-inflammatory and life-prolonging effects have been reported. Resveratrol synthase, competing with chalcone synthase for the same substrates, is the key enzyme to synthesize resveratrol. Resveratrol has beneficial effects on human health such as anti-cancer and antioxidant. Therefore, it is necessary to produce the compound in plant in which resveratrol is absent by plant engineering. Furthermore, our research demonstrate that resveratrol synthase is close connected with endophyte fungi in some plants, and we are trying to increase the quantity of resveratrol via improve the relationship between endophyte fungi and their hosts.1. Primers were designed according to the conserved sequence of Resveratrol synthase(RS) in grape and used to clone a RS gene coding region from Parthenocissus henryana by RT-PCR. The RS gene is 94% identical with resveratrol synthase gene of vitis at nucleotide acid level.2. Flanking by MARs, the RS gene under control of CaMV35S promoter has been transformed into Lactuca Sativa L. and the transgenic plants have been identified by PCR,RT-PCR and Northern blotting analysis. The results showed that the heterogeneous RS gene was normally expressed in transgenic plants. An additional compound whose retention time is the same as that of free trans-resveratrol standard was detected in transgenic plants by HPLC analysis, and ESI-MS analysis results confirmed that the compound was resveratrol because of the same m/z value with trans-resveratrol standard. Quantification showed that the highest resveratrol content ranged from 9.25±0.83 to 68.5±0.78μg/g leaf FW in lettuce.3. An endophytic fungi containing RS gene was isolated from Caulis Parthenocissi Tricuspidatae. The RS gene is 95.25% identical with resveratrol synthase gene of Caulis Parthenocissi Tricuspidatae at nucleotide acid level and 97.45% at protein level.The fungus belongs to Cladosporium sp. by 18S rDNA identification. The results of HPLC and ESI-MS demonstrate that the fungus can accumulates resveratrol without the host.