The monolignol pathway contributes to the biosynthesis of volatile phenylpropenes in flowers

© 2014 The Authors. New Phytologist © 2014 New Phytologist Trust.

Bibliographische Detailangaben
Veröffentlicht in:The New phytologist. - 1979. - 204(2014), 3 vom: 04. Nov., Seite 661-670
1. Verfasser: Muhlemann, Joëlle K (VerfasserIn)
Weitere Verfasser: Woodworth, Benjamin D, Morgan, John A, Dudareva, Natalia
Format: Online-Aufsatz
Sprache:English
Veröffentlicht: 2014
Zugriff auf das übergeordnete Werk:The New phytologist
Schlagworte:Journal Article Research Support, U.S. Gov't, Non-P.H.S. cinnamoyl-CoA reductase lignin monolignol biosynthesis petunia (Petunia hybrida) phenylpropanoid pathway phenylpropene volatile organic compounds Plant Proteins Propanols Volatile Organic Compounds
Beschreibung
Zusammenfassung:© 2014 The Authors. New Phytologist © 2014 New Phytologist Trust.
Volatile phenylpropenes play important roles in the mediation of interactions between plants and their biotic environments. Their biosynthesis involves the elimination of the oxygen functionality at the side-chain of monolignols and competes with lignin formation for monolignol utilization. We hypothesized that biochemical steps before the monolignol branch point are shared between phenylpropene and lignin biosynthesis; however, genetic evidence for this shared pathway has been missing until now. Our hypothesis was tested by RNAi suppression of the petunia (Petunia hybrida) cinnamoyl-CoA reductase 1 (PhCCR1), which catalyzes the first committed step in monolignol biosynthesis. Detailed metabolic profiling and isotopic labeling experiments were performed in petunia transgenic lines. Downregulation of PhCCR1 resulted in reduced amounts of total lignin and decreased flux towards phenylpropenes, whereas internal and emitted pools of phenylpropenes remained unaffected. Surprisingly, PhCCR1 silencing increased fluxes through the general phenylpropanoid pathway by upregulating the expression of cinnamate-4-hydroxylase (C4H), which catalyzes the second reaction in the phenylpropanoid pathway. In conclusion, our results show that PhCCR1 is involved in both the biosynthesis of phenylpropenes and lignin production. However, PhCCR1 does not perform a rate-limiting step in the biosynthesis of phenylpropenes, suggesting that scent biosynthesis is prioritized over lignin formation in petals
Beschreibung:Date Completed 01.06.2015
Date Revised 16.04.2021
published: Print-Electronic
Citation Status MEDLINE
ISSN:1469-8137
DOI:10.1111/nph.12913