Differential expression of the key genes involved in the biosynthesis of monoterpenes in different tissues and in response to abiotic elicitors in Summer savory (Satureja hortensis)

Aim: The aim of this study was to investigate the expression of key genes, 1-deoxy-D-xylulose-5-phosphate reductoisomerase )DXR( and gamma-terpinene synthase (GTS), involve in thymol and carvacrol biosynthesis pathway in Summer savory (Satureja hortensis). This species is one of the important medicinal plants of the Lamiaceae family, and consider as an important source of the mentioned compounds.
Material and Plants were treated with salicylic acid, methyl jasmonate and UV-B rays. RNAs were extracted from control and treated plants and cDNAs were synthesized. Primers were designed for gene isolation and expression studies. Transcript expression analyses for the DXR and GTS were performed using semi-quantitative RT-PCR method.
A partial segment for DXR and GTS genes was sequenced. The relative gene expression analyses showed differential expression of both genes at transcript level in different tissues (roots, stems, leaves and inflorescence), with higher levels of expression in leaf and inflorescence. The expression of both genes under the effect of abiotic elicitors including salicylic acid, methyl jasmonate and UV-B rays exhibited significant alteration.
Under controlled conditions, using abiotic elicitors such as: salicylic acid, methyl jasmonate and UV-B radiation could elevate the level of gene expression and possibly increase the production of secondary metabolite such as: thymol and carvacrol.