CYP94A1, a plant cytochrome P450-catalyzing fatty acid omega-hydroxylase, is selectively induced by chemical stress in Vicia sativa seedlings

• Published in: Planta Vol. 221; no. 6; pp. 881 - 890
• Main Authors: Benveniste, I, Bronner, R, Wang, Y, Compagnon, V, Michler, P, Schreiber, L, Salaun, J.P, Durst, F, Pinot, F
• Format: Journal Article
• Language: English
• Published: Berlin Springer-Verlag 01.08.2005; Springer
• Subjects: 2,3-dichlorophenoxyacetic acid; 2,4-D; 2,4-Dichlorophenoxyacetic Acid - pharmacology; Agronomy. Soil science and plant productions; antilipemic agents; Auxins; Biological and medical sciences; clofibrate; Clofibrate - pharmacology; cytochrome P-450; Cytochrome P-450 Enzyme System - biosynthesis; Cytochrome P-450 Enzyme System - metabolism; Economic plant physiology; Enzyme Induction - drug effects; Epicotyls; Epidermal cells; fatty acid omega-hydroxylase; Fatty acids; Fundamental and applied biological sciences. Psychology; gene expression regulation; Gene Expression Regulation, Developmental; Gene Expression Regulation, Plant - drug effects; Genes; Herbicides - pharmacology; hydroxylation; indole acetic acid; Indoleacetic Acids - pharmacology; Internodes; Messenger RNA; Mixed Function Oxygenases - biosynthesis; Mixed Function Oxygenases - metabolism; oxygenases; p-chlorophenoxyisobutyric acid; plant biochemistry; plant genetics; plant morphology; Plants; Protein isoforms; RNA, Messenger - metabolism; salicylic acid; Salicylic Acid - pharmacology; Seedlings; Seedlings - drug effects; Seedlings - enzymology; Time Factors; transcriptional activation; Vicia sativa; Vicia sativa - drug effects; Vicia sativa - enzymology; Water relations, transpiration, stomata; Salicylic acid; Auxin; Transcription; Enzyme; Growth; Vicia; Cytochrome P450; Hydroxylase; Chemical transcription activation; Fatty acids; Stress; Defense; Vicia sativa; Leguminosae; Alkane 1-monooxygenase; Dicotyledones; Angiospermae; Development; Spermatophyta; Oxidoreductases; Fatty acid hydroxylases
• ISSN: 0032-0935; 1432-2048
• DOI: 10.1007/s00425-005-1503-y

CYP94A1 is a cytochrome P450 (P450) catalyzing fatty acid (FA) omega-hydroxylation in Vicia sativa seedlings. To study the physiological role of this FA monooxygenase, we report here on its regulation at the transcriptional level (Northern blot). Transcripts of CYP94A1, as those of two other P450-dependent FA hydroxylases (CYP94A2 and CYP94A3) from V. sativa, are barely detectable during the early development of the seedlings. CYP94A1 transcripts, in contrast to those of the two other isoforms, are rapidly (less than 20 min) and strongly (more than 100 times) enhanced after treatment by clofibrate, an hypolipidemic drug in animals and an antiauxin (p-chlorophenoxyisobutyric acid) in plants, by auxins (2,4-dichlorophenoxyacetic acid and indole-3-acetic acid), by an inactive auxin analog (2,3-dichlorophenoxyacetic acid), and also by salicylic acid. All these compounds activate CYP94A1 transcription only at high concentrations (50-500 micromolar range). In parallel, these high levels of clofibrate and auxins modify seedling growth and development. Therefore, the expression of CYP94A1 under these conditions and the concomitant morphological and cytological modifications would suggest the implication of this P450 in a process of plant defense against chemical injury.