Gene Cloning Of Linalool Synthase From Lavender(Lavandula Spica)and Construction Of Plant Expression Vector

Lavandula spica, a kind of perennial herbage originating in Mediterranean, belonging to the lavender from the Family Labiatae, is hot and Submergence tolerance, which is a kind of lavender better adapted to the high temperature and humidity in Hainan. The whole plant of Lavandula spica could emit the pleasant fragrance with the effectiveness of striking refreshing_and relieving nervous. Linalool synthase usually extracted from leaves, flowers, fruit, and so on.It is a key enzyme,which can accept a single substrate geranyl diphosphate and transform it to a single product—linalool,under the condition of electrophilic mechanism. Linalool as a natural functional monoterpenes, is the main component of plant essential oils. So it has very high economic value and medicinal value, which is widely used in medicine, food, cosmetics and daily chemicals industry._In this experiment, the linalool synthase gene was extracted from the leaves of Lavandula spica, then cloning and sequences analysis of linalool synthase gene were performed. Then a plant expression vector of linalool synthase gene was constructed uccessfully. This study was targeted to clone the linalool synthase gene and construct the gene transfer vector, so to lay a foundation for the genetic advance of tropical landscape plants with no fragrance or lighter fragrance species. The main research results were as follows:1,According to the linalool synthase homologous sequences, specific primers were designed, then linalool synthase gene was successfully cloned from the leaves of lavandula spica through the RT-PCR technology, which cDNA sequence was1809bp, encoding602amino acids, with a complete open reading frame sequence.2,protein sequences of the linalool synthase gene cloned by lavandula spica was compared with others. The sequence has all conserved amino acid function sequences of the monoterpene synthase, including DDXXD and the5'RR functionalgroup and (N, D) D (L, I, V) X (S, T) XXXE and other highly conserved functional domains, belonging to the linalool synthase family. The results of predicted secondary structure for Lllis and Lslis showed that both the mostly structures kept consistent, but Lslis had less a a helix than Lllis. so linalool synthase gene from lavandula spica was named Lslis.3,Using the binary expression vector (including CaMV35S promoter and NOS Terminator) of plant expression vector pCAMBIA1303, the sense Lslis plant expression vectors were constructed and transferred into Agrobacterium LBA4404by electroporation.