Gene ID:
BankIt2292418 LaTPS7 MN822897
BankIt2292495 LaTPS8 MN822898
BankIt2292498 LaCYP71D582 MN822899
Abstract
To protect themselves from herbivore attacks, especially during early developmental stages, plants produce volatiles possessing various ecological and physiological functions. Here, we identified three genes cloned from Lavandula angustifolia . These genes, designated asLaTPS7 , LaTPS8 , and LaCYP71D582 , were hypothesized to be active in plant defense during early developmental stages. Thein-vitro assays showedLa TPS7 produced eight compounds including camphene, myrcene, limonene etc. and La TPS8 catalyzed nine volatiles fromα -pinene, sylvestrene to fenchol etc. using geranyl diphosphate (GPP) and nerolidyl diphosphate (NPP) as substrate separately. However,La TPS7 present in plastids only, synthesized limonene withinNicotiana benthamiana . Limonene was then converted into carveol byLa CYP71D582 present in the endoplasmic reticulum. La TPS8, also located in plastids, synthesized α -pinene and sylvestrene. Odour response of aphids (Myzus persicae ) and ladybugs (Harmonia axyridis ) showed that volatiles from transgenic tobacco leaves repelled aphids and attracted ladybugs. LaTPS7 promoter GUS stain assay inArabidopsis thaliana showed that LaTPS7 displayed a wound-induced expression in leaves. Together, our findings show that these compounds and gene-expression pattern played important roles in protecting plants during vulnerable stages. More practically, these plant tactics can be exploited in agriculture to decrease the use of insecticides, thereby contributing to improved human and environmental health.
Key words : lavender, monoterpenes, terpene synthase, cytochrome P450, insects plant-herbivore-natural enemy tritrophic interaction