Lipid-derived signals that discriminate wound- and pathogen-responsive isoprenoid pathways in plants: methyl jasmonate and the fungal elicitor arachidonic acid induce different 3-hydroxy-3-methylglutaryl-coenzyme A reductase genes and antimicrobial isoprenoids in Solanum tuberosum L.

Abstract

Induction of 3-hydroxy-3-methylglutarylcoenzyme A reductase (HMGR; EC 1.

Differential Activity of Peroxidase Isozymes in Response to Wounding, Gypsy Moth, and Plant Hormones in Northern Red Oak (Quercus rubra L.)

“…In addition, generalized soluble or wall-bound POD activity increases in other plant species in response to wounding (Birecka and Miller, 1974;Kawaoka et al, 1994), pathogens (Bashan et al, 1987), salicylic acid (Rao et al, 1997), and jasmonates (Thaler et al, 1996;Moore et al, 2003). While JA and insect wounding have been found to elevate total soluble POD activity similarly (Choi et al, 1994;Tamari et al, 1995;Zhang and Baldwin, 1997), this study is among the first to suggest that various peroxidase isozymes may be differentially responsive to JA or other signals (Buzi et al, 2004) and the first to find insectresponsive POD isoforms. Our results also indicate that JA does not elicit POD isozymes in exactly the same manner as does gypsy moth herbivory.…”

“…Isoform A3.9 activity was enhanced by treatment with SA (P = 0.055), a signal more associated with plant defense responses to microbes (Enyedi et al, 1992;Choi et al, 1994;Conti et al, 1996). It is possible, although unlikely, that our trees were incidentally infected by microbes during that particular treatment despite sterilizing the leaf punch, and that A3.9 is both wound-and microberesponsive.…”

The Role of Octadecanoids and Functional Mimics in Soybean Defense Responses

“…In potato discs, distinct effects on the activation of single members of the 3-hydroxy-3-methylglutaryl-coenzyme A reductase gene family were reported for JAMe versus the fungal elicitor, arachidonic acid, leading to different metabolite profiles suggesting distinct signaling pathways (Choi et al, 1994). In barley (Hordeum vulgare cv.…”

Envelope Membranes from Spinach Chloroplasts Are a Site of Metabolism of Fatty Acid Hydroperoxides

“…This new pathway involves (a) a peroxygenase, which catalyzes an intramolecular transfer of one oxygen atom from fatty acid hydroperoxides, yielding an epoxyalcohol and Jor co-oxidation reactions such as epoxidation of double bonds of unsaturated fatty acids , and (b) an epoxide hydrolase, which preferentially hydrates the epoxides formed by the peroxygenase (Blée and Schuber, 1992a). Lipid-breakdown metabolism is generally enhanced under stress conditions (Ohta et al, 1991;Farmer and Ryan, 1992a;Croft et al, 1993;Choi et al, 1994). At present, it seems that peroxygenase and hydroperoxide lyase pathways are involved in the response to pathogen infection (Ohta et al, 1991;Croft et al, 1993), and the hydroperoxide dehydratase cascade operates in wound-response programs (Farmer and Ryan, 1992a;Choi et al, 1994).…”

“…Lipid-breakdown metabolism is generally enhanced under stress conditions (Ohta et al, 1991;Farmer and Ryan, 1992a;Croft et al, 1993;Choi et al, 1994). At present, it seems that peroxygenase and hydroperoxide lyase pathways are involved in the response to pathogen infection (Ohta et al, 1991;Croft et al, 1993), and the hydroperoxide dehydratase cascade operates in wound-response programs (Farmer and Ryan, 1992a;Choi et al, 1994). Plant organelles such as chloroplasts may be a site of biosynthesis of regulatory molecules potentially involved in plant-defense reactions, since lipoxygenase, hydroperoxide lyase, and dehydratase activities have been measured in chloroplast preparations (Vick and Zimmerman, 1987;Bowsher et al, 1992;Hatanaka, 1993;Song et al, 1993).…”