Differential Response of Cultured Parsley Cells to Elicitors from Two Non-pathogenic Strains of Fungi. 1. Identification of Induced Products as Coumarin Derivatives

Abstract

Dark‐grown cell suspension cultures of parsley, Petroselinum hortense, produce furanocoumarins after treatment with elicitor preparations of either Phytophthora megasperma f.sp. glycinea (Pmg elicitor) or Alternaria carthami Chowdhury (Ac elicitor). The linear furanocoumarins, psoralen and xanthotoxin, and the benzodipyrandione, graveolone, are the major products synthesized in response to Pmg elicitor, besides small amounts of the furanocomarin bergapten. Treatment with Ac elicitor induces predominantly the formation of bergapten and the furanocoumarin isopimpinellin, as well as small amounts of graveolone. While Pmg elicitor leads to cell death within a few days, cell mass increased for at least 6 days after treatment with Ac elicitor. Brefeldin A, a phytotoxin produced by A. carthami, inhibits growth of parsley cell suspension cultures considerably at a concentration of 0.01 mM and growth of the cells ceased at a concentration of 0.1 mM toxin. Concomitantly, furanocoumarin biosynthesis was suppressed in our system by a concentration of brefeldin A within 0.01–0.1 mM.

Metabolic changes in elicitor-treated bean cells. Selectivity of enzyme induction in relation to phytoalexin accumulation

“…It is quite striking that elicitor further induces the activities of phenylalanine ammonia-lyase and chalcone isomerase, while at the same time preventing the increases in glutamate dehydrogenase and p-coumarate 3-monooxygenase [ 121, two enzymes not involved in the isoflavonoid branch pathway of phenolic synthesis. This phenomenon of elicitor-mediated selective induction of enzymes of phytoalexin formation, coupled with inhibition of appearance of enzymes not directly involved in phytoalexin synthesis, is even more strikingly apparent in parsley cell cultures, where elicitor induces the appearance of furanocoumarin phytoalexins [40] but prevents the lightmediated induction of chalcone synthase and acetyl-CoA carboxylase [41], these enzymes being involved in flavonoid, but not furanocoumarin, formation in parsley.…”

Characterization and Expression of Caffeoyl-Coenzyme A 3-O-Methyltransferase Proposed for the Induced Resistance Response of Vitis vinifera L

“…Resveratrol and related phenolics started to accumulate after about 6 to 9 h under these conditions, and the yellow-white cells and the culture broth turned brown (data not shown). In contrast to many other plant cells (Tietjen et al, 1983;Graham and Graham, 1991) COMT and, in particular, CCoAOMT activities have been commonly considered as indicators of phenylpropanoid synthesis and lignification (Ye et al, 1994;Boudet et al, 1995;Matern et al, 1995). Low constitutive activities of both CCoAOMT and COMT were determined for the cultured grapevine cells (Fig.…”

Induction of phenylalanine ammonia-lyase and 4-coumarate:CoA ligase mRNAs in cultured plant cells by UV light or fungal elicitor

“…Cell suspension cultures of parsley (Petroselinum hortense) produce and accumulate either flavonoids, when treated with UV light (1), or furanocoumarins, when treated with a fungal elicitor preparation (2). Flavonoids may be involved in protecting a plant from excess UV irradiation (3).…”

“…Flavonoids may be involved in protecting a plant from excess UV irradiation (3). Furanocoumarins are the putative phytoalexins (antimicrobial substances) of parsley (2) and could protect the plant from fungal attack. Neither flavonoids nor furanocoumarins are found in uninduced cells, and activities of the enzymes involved in flavonoid or furanocoumarin production are low or undetectable (1,4).…”