Expression in Arabidopsis of a Strawberry Linalool Synthase Gene Under the Control of the Inducible Potato PI2 Promoter

To investigate the role of inducible linalool in Arabidopsis-insect interactions, the FaNES1 linalool synthase (LIS) cDNA from strawberry with plastid targeting and a synthetic intron (LIS') was placed under the control of the wound inducible proteinase inhibitor 2 (PI2) promoter from potato. The construct pBin-PPI2-LIS' was transformed to Arabidopsis thaliana ecotype Columbia 0. Kanamycin resistant T0 seedlings were confirmed for the presence and transcription of the LIS' gene by PCR analysis on genomic DNA and by RT-PCR analysis on RNA. Genomic and RT-PCR products were sequenced to confirm correct splicing of the synthetic intron. The expression of active linalool synthase by the PPI2-LIS' gene construct in the transgenic lines was assessed by measuring linalool emission using solid phase micro-extraction (SPME) GC-MS measurements after induction with methyl jasmonate. Among 30 tested independent T2 transgenic lines, 10 exhibited linalool production. Linalool expression could be induced by methyl jasmonate treatment, but not by diamondback moth larvae.