[PERSON]  
[PERSON]  
1 Institute for Biological Research \"[PERSON]\"-National Institute of Republic of Serbia, University of Belgrade, Bulevar despota Stefana 142, 11060 Belgrade, Serbia; [EMAIL_ADDRESS] (J.B.); [EMAIL_ADDRESS] (D.M. ); [EMAIL_ADDRESS] (S.Z. ); [EMAIL_ADDRESS] (M.D. ); [EMAIL_ADDRESS] (N.A. ); [EMAIL_ADDRESS] (N.A. ); [EMAIL_ADDRESS] (B.F); [EMAIL_ADDRESS] (T.  
the first secoriidoid compound in the pathway--secologanin (3). Further biosynthetic route from secologanin (3) to sweroside (4), swertiamarin (5), and gentiopicrin (6) is not fully elucidated. In _Catharantthus roseus_, secologanin is a universal precursor of monoterenoid indole alkaloids (MIAs) [7], and genes that are involved in the biosynthesis of secologanin have been thoroughly studied [8; 9; 10]. Recently, we have identified genes encoding for enzymes of the SGs biosynthetic pathway up to secologanin in _C. erythraea_ leaves transcriptome, including geranyl diphosphate synthase (_CeGPPS_), geraniol synthase (_CeGES_), geraniol-8-oxidase (_CeGSO_), 8-hydrohygeraniol oxidoreductase (_Ce8 HGO_), iridoid synthase (_CeI_S), iridoid oxidase (_CeI_O), 7-deoxyloganetic acid glucosyltransferase (_Ce7 DLGT_), two candidates for 7-deoxyloganic acid hydrolase (_Ce7 DLH1_ and _Ce7 DLH2_), loganic acid O-methyltransferasease (_CeLAMT_), and secologanin synthase (_CeSLS_) [4]. Organ-specific and genotype-dependent regulation of SGs biosynthesis was demonstrated [4]. The constitutive production of extremely bitter secoriidoid glucosides in _C. erythraea_, as a part of defense strategy, provides continuous and efficient protection against pathogens and herbivores. As an integral part of plant defense itself, these chemicals prevent herbivory, most likely by deterring feeding that is based on the bitter taste aversion. The deterrent effects of iridoid glycosides on generalist and non-adapted specialist insect herbivores are well-documented [11; 12; 13; 14; 15]. A series of mechanisms directed to heal the tissues and prevent further damage are promptly activated once the leaf tissues are wounded/injured [16; 17]. Wounding-induced effects might also occur in response to some other abiotic (wind, storm, strong rain) or biotic factors (anthropogenic intrusion) since plants are sessile organisms, continuously exposed to various unfavorable environmental conditions. Common centaury grows in open, often transient, temporary habitats with cleared areas, such as dry pastures, early successive stages of establishing forest vegetation (e.g., after deforestation), forest edges, roads and paths, slopes or open forests, channel sides, newly built roads, etc. [18; 19]. Thus, it is often exposed to moving, which results in the wounding of stems and leaves, stimulation of lateral shoots growth and branching, and the inducing of changes in overall physiology and biochemistry. Generally, responses to wounding occur both in the injured tissue (local response) and in the undamaged areas (systemic response) [16; 20]. Most of these responses occur after several seconds to minutes, or in some cases even several hours after wounding [21; 22; 23; 24]. They start with generation, following the perception and transduction of specific signals, and lead to an alteration of expression of numerous genes [21; 24; 25]. Some of these genes are rapidly affected, including genes that are involved in the biosynthesis of jasmonic acid (JA) and ethylene (ET), as well as those that are involved in the general stress responses [21; 23; 25]. Thereafter, the modulation of expression of genes that are involved in specialized metabolites biosynthesis pathways (e.g., glucosinolates, alkaloids, phenolic compounds) could be noticed, together with the alterations in the primary metabolism (carbohydrate and lipid metabolism, nitrogen assimilation) [17; 22; 25]. Specialized metabolites biosynthesis is predominantly controlled at the transcriptional level by the action of specific transcription factors (TFs) [26].