Gene-specific involvement of beta-oxidation in wound-activated responses in Arabidopsis.
The coordinated induced expression of beta-oxidation genes is essential to provide the energy supply for germination and postgerminative development. However, very little is known about other functions of beta-oxidation in nonreserve organs. We have identified a gene-specific pattern of induced beta-oxidation gene expression in wounded leaves of Arabidopsis. Mechanical damage triggered the local and systemic induction of only ACX1 among acyl-coenzyme A oxidase (ACX) genes, and KAT2/PED1 among 3-ketoacyl-coenzyme A thiolase (KAT) genes in Arabidopsis. In turn, wounding induced KAT5/PKT2 only systemically. Although most of the beta-oxidation genes were activated by wound-related factors such as dehydration and abscisic acid, jasmonic acid (JA) induced only ACX1 and KAT5. Reduced expression of ACX1 or KAT2 genes, in transgenic plants expressing their corresponding mRNAs in antisense orientation, correlated with defective wound-activated synthesis of JA and with reduced expression of JA-responsive genes. Induced expression of JA-responsive genes by exogenous application of JA was unaffected in those transgenic plants, suggesting that ACX1 and KAT2 play a major role in driving wound-activated responses by participating in the biosynthesis of JA in wounded Arabidopsis plants.
Cruz Castillo
M
M
Instituto de Biología Molecular y Celular de Plantas, 46022 Valencia, Spain.
Martínez
Cristina
C
Buchala
Antony
A
Métraux
Jean-Pierre
JP
León
José
J
D000040:Abscisic Acid / Q000494:pharmacology; D042962:Acyl-CoA Oxidase / Q000235:genetics / Q000378:metabolism; D016375:Antisense Elements (Genetics) / Q000235:genetics; D017360:Arabidopsis / Q000201:enzymology / Q000235:genetics*; D029681:Arabidopsis Proteins / Q000235:genetics* / Q000378:metabolism; D003517:Cyclopentanes / Q000494:pharmacology; D003681:Dehydration; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D054883:Oxylipins; D010937:Plant Growth Regulators / Q000494:pharmacology; D030821:Plants, Genetically Modified; D015221:Potassium Channels / Q000235:genetics / Q000378:metabolism; D024642:Potassium Channels, Voltage-Gated; D013314:Stress, Mechanical
D016375:Antisense Elements (Genetics); D029681:Arabidopsis Proteins; D003517:Cyclopentanes; C428126:KAT2 protein, Arabidopsis; D054883:Oxylipins; D010937:Plant Growth Regulators; D015221:Potassium Channels; D024642:Potassium Channels, Voltage-Gated; C011006:jasmonic acid; D000040:Abscisic Acid; D042962:Acyl-CoA Oxidase