Alterations in nepetalactone metabolism during polyethylene glycol (PEG)-induced dehydration stress in two Nepeta species. (June 2020)

• Record Type: Journal Article
• Authors: Aničić, Neda; Matekalo, Dragana; Skorić, Marijana; Živković, Jasmina Nestorović; Petrović, Luka; Dragićević, Milan; Dmitrović, Slavica; Mišić, Danijela
• Is Part Of: Phytochemistry. Volume 174(2020)
• Publication Date: 2020-06
• Subjects: Nepeta rtanjensis -- Nepeta argolica ssp. argolica -- Lamiaceae -- Iridoid monoterpenoids -- Nepetalactone biosynthesis -- Transcription factors -- Dehydration stress -- PEG; Botanical chemistry -- Periodicals; Biochemistry -- Periodicals; Botany -- Periodicals; Chimie végétale -- Périodiques; 572.2
• DOI: 10.1016/j.phytochem.2020.112340
• Languages: English
• ISSNs: 0031-9422

Abstract

Abstract: A number of Nepeta species (fam. Lamiaceae) are interesting medicinal crops for arid and semi-arid areas, due to their ability to maintain essential developmental and physiological processes and to rationalize their specialized metabolism under water deficit growth conditions. The present research is, to our knowledge, the first attempt to investigate the molecular background of the dehydration-induced changes in specialized metabolism of Nepeta species, which will help to understand relations between dehydration stress on one hand and biomass production and yield of nepetalactone (NL) on the other. During the 6 days exposure of Nepeta rtanjensis Diklić & Milojević and Nepeta argolica Bory & Chaub. ssp. argolica plants to PEG-induced dehydration stress under experimental in vitro conditions, decrease in transcript levels of the majority of 10 NL biosynthetic genes, and some of the 5 transcription factors (TFs) were recorded, simultaneously with the initial reduction in NL content. The two model species evidently employ similar strategies in response to severe dehydration stress; however N. rtanjensis is highlighted as the species more efficient in maintaining NL amounts in tissues. The results suggest trichome-specific and co-ordinately regulated NL biosynthesis at the level of gene expression, with trichome enriched MYC2 and YABBY5 TFs being the potential positive regulators. Manipulation of such TFs can be effective for engineering the NL biosynthetic pathway, and for the increased production of cis, trans -NL in N. argolica ssp . argolica and trans, cis -NL in N. rtanjensis . Graphical abstract: Image 1 Highlights: Nepeta rtanjensis and N. argolica ssp. argolica differ in major NLs stereochemistry. NL biosynthetic genes are coordinately downregulated in response to dehydration. Nepetalactone biosynthesis is regulated at the gene expression level. Transcription factors YABBY5 and MYC2 are positive regulators of NL biosynthesis. N. rtanjensis is more efficient in maintaining NL amounts during dehydration stress.