Salvia mirzayanii is a medicinal and aromatic plant with many pharmaceutical properties. The aims of this study were to isolate and characterise a specific gene involved in biosynthesis of major terpenoids produced by S. mirzayanii under increasing salinity stress, followed by investigation of photosynthetic responses under which yield of these terpenoids increased. Plants were grown in a greenhouse and harvested after 3 weeks’ exposure to different levels of salinity stress (25, 50, 75, and 100 mM NaCl). The isolation and expression analysis by RT-PCR of cineole synthase 1 gene (SmCin1), in response to 75 mM NaCl treatment, was investigated. Results showed that although the net photosynthesis and chlorophyll concentration decreased when salt stress severity increases, the amount of major terpenoids, α-terpinyl acetate, 1,8-cineole, and linalyl acetate increased. Expression analysis showed that SmCin1 transcript accumulated in leaves by approximately 11-fold during early hours of salinity treatment compared with non-treated (control) plants. The phylogenetic and sequence alignment analyses revealed that SmCin1 (GenBank accession no. KT438251.1) is closely aligned with other Salvia Cin1 genes in the GenBank (45–100%). These findings could be applied in economic cultivation, breeding programmes, and genetic engineering of S. mirzayanii to produce higher yields of terpenoids.

The medicinal plantDigitalis purpureaproduces cardiac glycosides that are useful in the pharmaceutical industry. These bioactive compounds are in high demand due to ethnobotany’s application to therapeutic procedures. Recent studies have investigated the role of integrative analysis of multi-omics data in understanding cellular metabolic status through systems metabolic engineering approach, as well as its application to genetically engineering metabolic pathways. In spite of numerous omics experiments, most molecular mechanisms involved in metabolic pathways biosynthesis inD.purpurearemain unclear. Using R Package Weighted Gene Co-expression Network Analysis, co-expression analysis was performed on the transcriptome and metabolome data. As a result of our study, we identified transcription factors, transcriptional regulators, protein kinases, transporters, non-coding RNAs, and hub genes that are involved in the production of secondary metabolites. Since jasmonates are involved in the biosynthesis of cardiac glycosides, the candidate genes forScarecrow-Like Protein 14(SCL14),Delta24-sterol reductase(DWF1),HYDRA1(HYD1), and Jasmonate-ZIM domain3 (JAZ3) were validated under methyl jasmonate treatment (MeJA, 100 μM). Despite early induction ofJAZ3, which affected downstream genes, it was dramatically suppressed after 48 hours.SCL14, which targetsDWF1, andHYD1, which induces cholesterol and cardiac glycoside biosynthesis, were both promoted. The correlation between key genes and main metabolites and validation of expression patterns provide a unique insight into the biosynthesis mechanisms of cardiac glycosides inD.purpurea.

Medicinal plants contain valuable compounds that have attracted worldwide interest for their use in the production of natural drugs. The presence of compounds such as rosmarinic acid, carnosic acid, and carnosol in Rosmarinus officinalis has made it a plant with unique therapeutic effects. The identification and regulation of the biosynthetic pathways and genes will enable the large-scale production of these compounds. Hence, we studied the correlation between the genes involved in biosynthesis of the secondary metabolites in R. officinalis using proteomics and metabolomics data by WGCNA. We identified three modules as having the highest potential for the metabolite engineering. Moreover, the hub genes highly connected to particular modules, TFs, PKs, and transporters were identified. The TFs of MYB, C3H, HB, and C2H2 were the most likely candidates associated with the target metabolic pathways. The results indicated that the hub genes including Copalyl diphosphate synthase (CDS), Phenylalanine ammonia lyase (PAL), Cineole synthase (CIN), Rosmarinic acid synthase (RAS), Tyrosine aminotransferase (TAT), Cinnamate 4-hydroxylase (C4H), and MYB58 are responsible for biosynthesis of important secondary metabolites. Thus, we confirmed these results using qRT-PCR after treating R. officinalis seedlings with methyl jasmonate. These candidate genes may be employed for genetic and metabolic engineering research to increase R. officinalis metabolite production.

Biotic stresses are pests and pathogens that cause a variety of crop diseases and damages. In response to these agents, crops trigger specific defense signal transduction pathways in which hormones play a central role. To recognize hormonal signaling, we integrated barley transcriptome datasets related to hormonal treatments and biotic stresses. In the meta-analysis of each dataset, 308 hormonal and 1232 biotic DEGs were identified respectively. According to the results, 24 biotic TFs belonging to 15 conserved families and 6 hormonal TFs belonging to 6 conserved families were identified, with the NF-YC, GNAT, and WHIRLY families being the most prevalent. Additionally, gene enrichment and pathway analyses revealed that over-represented cis-acting elements were recognized in response to pathogens and hormones. Based on the co-expression analysis, 6 biotic and 7 hormonal modules were uncovered. Finally, the hub genes of PKT3, PR1, SSI2, LOX2, OPR3, and AOS were candidates for further study in JA- or SA-mediated plant defense. The qPCR confirmed that the expression of these genes was induced from 3 to 6 h following exposure to 100 μM MeJA, with peak expression occurring between 12 h and 24 h and decreasing after 48 h. Overexpression of PR1 was one of the first steps toward SAR. As well as regulating SAR, NPR1 has also been shown to be involved in the activation of ISR by the SSI2. LOX2 catalyzes the first step of JA biosynthesis, PKT3 plays an important role in wound-activated responses, and OPR3 and AOS are involved in JA biosynthesis. In addition, many unknown genes were introduced that can be used by crop biotechnologists to accelerate barley genetic engineering.