Effect of nanoparticle treatment on expression of a key gene involved in thymoquinone biosynthetic pathway in Nigella sativa L.

Thymoquinone is the most important secondary metabolite in black Cumin, which has several pharmaceutical applications. In this study, effect of TiO₂ and SiO₂ nanoparticles as new elicitors, on expression of Geranyl diphosphate synthase gene (GPPS gene), as a key gene involved in thymoquione biosynthesis pathway was investigated in two Iranian accessions. Plants were treatment in the early flowering stage and after 24 h of 50 and 100 mg/L of each nanoparticle, separately. After RNA extraction, GPPS gene expression was analysed by qRT-PCR method. The results showed that the TiO₂ and SiO₂ nanoparticles, generally stimulates the GPPS expression. The TiO₂ nanoparticles were more effective than SiO₂ for the induction of GPPS expression. Also, 100 mg/L treatment of nanoparticles raised gene expression more than 50 mg/L concentration. It can be concluded these nanoparticles can be used as robust elicitors to enhance the production of Thymoquinone in black cumin through up-regulation of related metabolic pathway genes.