Secoiridoids Metabolism Response to Wounding in Common Centaury (Centaurium erythraea Rafn) Leaves

Abstract

Centaurium erythraea Rafn produces and accumulates various biologically active specialized metabolites, including secoiridoid glucosides (SGs), which help plants to cope with unfavorable environmental conditions. Specialized metabolism is commonly modulated in a way to increase the level of protective metabolites, such as SGs. Here, we report the molecular background of the wounding-induced changes in SGs metabolism for the first time. The mechanical wounding of leaves leads to a coordinated up-regulation of SGs biosynthetic genes and corresponding JA-related transcription factors (TFs) after 24 h, which results in the increase of metabolic flux through the biosynthetic pathway and, finally, leads to the elevated accumulation of SGs 96 h upon injury. The most pronounced increase in relative expression was detected for secologanin synthase (CeSLS), highlighting this enzyme as an important point for the regulation of biosynthetic flux through the SG pathway. A similar expression pattern was observed for CeBIS1, imposing itself as the TF that is prominently involved in wound-induced regulation of SGs biosynthesis genes. The high degree of positive correlations between and among the biosynthetic genes and targeted TFs expressions indicate the transcriptional regulation of SGs biosynthesis in response to wounding with a significant role of CeBIS1, which is a known component of the jasmonic acid (JA) signaling pathway.

Functional Characterization of Genes Coding for Novel β-D-Glucosidases Involved in the Initial Step of Secoiridoid Glucosides Catabolism in Centaurium erythraea Rafn

“…In parallel, content of major secoiridoids (SW, SWM, and GP) was significantly higher in shoots than in roots of both diploid and tetraploid C. erythraea genotypes ( Figure 5B ). It is well documented that aerial parts are the major site of SGs biosynthesis and accumulation in common centaury ( Šiler et al, 2012 , 2014 ; Matekalo et al, 2018 ; Božunović et al, 2019 ; Filipović et al, 2019 ). Similarly, as in our previous study ( Božunović et al, 2019 ), the dominant SG in leaves of diploid and tetraploid plants was SW, followed by GP and SWM.…”

“…It is well documented that aerial parts are the major site of SGs biosynthesis and accumulation in common centaury ( Šiler et al, 2012 , 2014 ; Matekalo et al, 2018 ; Božunović et al, 2019 ; Filipović et al, 2019 ). Similarly, as in our previous study ( Božunović et al, 2019 ), the dominant SG in leaves of diploid and tetraploid plants was SW, followed by GP and SWM. Diploid plants displayed slightly higher GP content in shoots than tetraploid ones, which is in accordance with our previous study ( Filipović et al, 2019 ), and higher content of SW in roots compared to tetraploids.…”

Monoterpene glucosides accumulated inEustoma grandiflorumroots promote hyphal branching in arbuscular mycorrhizal fungi

“…Gene Ontology (GO) enrichment analysis revealed increases in UDP-glucosyltransferase activity and the production of secologanin, a precursor of secoiridoid glucosides including GPS and SWM (Fig. 1A and Supplemental Table S2) (De Luca et al, 2014;Cao et al, 2016;Rai et al, 2016;Božunović et al, 2019). In addition, the GO terms included secologanin biosynthetic genes annotated as 7-deoxyloganetic acid glucosyltransferase (7DLGT) and secologanin synthase (SLS) (De Luca et al, 2014) (Supplemental Table S3).…”