Copper amine oxidase expression in defense responses to wounding and Ascochyta rabiei invasion.
Wounding chickpea (Cicer arietinum) internodes or cotyledons resulted in an increase in the steady-state level of copper amine oxidase (CuAO) expression both locally and systemically. Dissection of the molecular mechanisms controlling CuAO expression indicated that jasmonic acid worked as a potent inducer of the basal and wound-inducible CuAO expression, whereas salicylic acid and abscisic acid caused a strong reduction of the wound-induced CuAO expression, without having any effect on the basal levels. Epicotyl treatment with the CuAO mechanism-based inhibitor 2-bromoethylamine decreased hydrogen peroxide (H(2)O(2)) levels in all the internodes, as evidenced in vivo by 3,3'-diaminobenzidine oxidation. Moreover, inhibitor pretreatment of wounded epicotyls resulted in a lower accumulation of H(2)O(2) both at the wound site and in distal organs. In vivo CuAO inhibition by 2-bromoethylamine after inoculation of resistant chickpea cv Sultano with Ascochyta rabiei resulted in the development of extended necrotic lesions, with extensive cell damage occurring in sclerenchyma and cortical parenchyma tissues. These results, besides stressing the fine-tuning by key signaling molecules in wound-induced CuAO regulation, demonstrate that local and systemic CuAO induction is essential for H(2)O(2) production in response to wounding and indicate the relevance of these enzymes in protection against pathogens.
Rea
Giuseppina
G
Dipartimento di Biologia, Università degli Studi Roma Tre, Viale Guglielmo Marconi 446, 00146 Rome, Italy.
Metoui
Ouissal
O
Infantino
Alessandro
A
Federico
Rodolfo
R
Angelini
Riccardo
R
D015100:3,3'-Diaminobenzidine / Q000378:metabolism; D000040:Abscisic Acid / Q000494:pharmacology; D006631:Amine Oxidase (Copper-Containing) / Q000037:antagonists & inhibitors / Q000235:genetics* / Q000378:metabolism; D029863:Cicer / Q000201:enzymology* / Q000235:genetics / Q000382:microbiology; D003517:Cyclopentanes / Q000494:pharmacology; D005021:Ethylamines / Q000494:pharmacology; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects; D006651:Histocytochemistry; D006861:Hydrogen Peroxide / Q000378:metabolism; D007113:Immunity, Innate; D003904:Mitosporic Fungi / Q000254:growth & development*; D054883:Oxylipins; D010935:Plant Diseases / Q000382:microbiology; D010937:Plant Growth Regulators / Q000494:pharmacology; D018547:Plant Stems / Q000201:enzymology / Q000235:genetics / Q000382:microbiology; D012333:RNA, Messenger / Q000187:drug effects / Q000235:genetics / Q000378:metabolism; D020156:Salicylic Acid / Q000494:pharmacology; D015398:Signal Transduction / Q000187:drug effects; D013997:Time Factors
D003517:Cyclopentanes; D005021:Ethylamines; D054883:Oxylipins; D010937:Plant Growth Regulators; D012333:RNA, Messenger; C004504:2-bromoethylamine; D015100:3,3'-Diaminobenzidine; C011006:jasmonic acid; D000040:Abscisic Acid; D006861:Hydrogen Peroxide; D006631:Amine Oxidase (Copper-Containing); D020156:Salicylic Acid