Molecular characterization of a Novel NAD+-dependent farnesol dehydrogenase SoFLDH gene involved in sesquiterpenoid synthases from Salvia officinalis.

Salvia officinalis is one of the most important medicinal and aromatic plants in terms of nutritional and medicinal value because it contains a variety of vital active ingredients. Terpenoid compounds, particularly monoterpenes (C10) and sesquiterpenes, are the most important and abundant among these active substances (C15). Terpenes play a variety of roles and have beneficial biological properties in plants. With these considerations, the current study sought to clone theNAD+-dependent farnesol dehydrogenase (SoFLDH, EC: 1.1.1.354) gene from S. officinalis. Functional analysis revealed that, SoFLDH has an open reading frame of 2,580 base pairs that encodes 860 amino acids.SoFLDH has two conserved domains and four types of highly conserved motifs: YxxxK, RXR, RR (X8) W, TGxxGhaG. However, SoFLDH was cloned from Salvia officinalis leaves and functionally overexpressed in Arabidopsis thaliana to investigate its role in sesquiterpenoid synthases. In comparison to the transgenic plants, the wild-type plants showed a slight delay in growth and flowering formation. To this end, a gas chromatography-mass spectrometry analysis revealed that SoFLDH transgenic plants were responsible for numerous forms of terpene synthesis, particularly sesquiterpene. These results provide a base for further investigation on SoFLDH gene role and elucidating the regulatory mechanisms for sesquiterpene synthesis in S. offcinalis. And our study paves the way for the future metabolic engineering of the biosynthesis of useful terpene compounds in S. offcinalis.

Overexpression of chalcone isomerase A gene in Astragalus trigonus for stimulating apigenin.

Apigenin is one of the most studied flavonoids and is widely distributed in the plant kingdom. Apigenin exerts important antioxidant, antibacterial, antifungal, antitumor activities, and anti-inflammatory effects in neurological or cardiovascular disease. Chalcone isomerase A (chiA) is an important enzyme of the flavonoid biosynthesis pathway. In order to enhance the apigenin production, the petunia chi A gene was transformed for Astragalus trigonus. Bialaphos survived plants were screened by PCR, dot blot hybridization and RT-PCR analysis. Also, jasmonic acid, salicylic acid, chitosan and yeast extract were tested to evaluate their capacity to work as elicitors for apigenin. Results showed that yeast extract was the best elicitor for induction of apigenin with an increase of 3.458 and 3.9 fold of the control for calli and cell suspension culture, respectively. Transformed cell suspension showed high apigenin content with a 20.17 fold increase compared to the control and 6.88 fold more than the yeast extract treatment. While, transformed T1 calli derived expressing chiA gene produced apigenin 4.2 fold more than the yeast extract treatment. It can be concluded that the highest accumulation of apigenin was obtained with chiA transgenic cell suspension system and it can be utilized to enhancement apigenin production in Astragalus trigonus.