title: Jasmonate response locus JAR1 and several related Arabidopsis genes encode enzymes of the firefly luciferase superfamily that show activity on jasmonic, salicylic, and indole-3-acetic acids in an assay for adenylation.
abstract: Jasmonic acid (JA) and related cyclopentanones are critical plant signaling molecules, but their mode of action at the molecular level is unclear. A map-based approach was used to identify the defective gene in the Arabidopsis JA response mutant jar1-1. JAR1 is 1 of 19 closely related Arabidopsis genes that are similar to the auxin-induced soybean GH3 gene. Analysis of fold predictions for this protein family suggested that JAR1 might belong to the acyl adenylate-forming firefly luciferase superfamily. These enzymes activate the carboxyl groups of a variety of substrates for their subsequent biochemical modification. An ATP-PPi isotope exchange assay was used to demonstrate adenylation activity in a glutathione S-transferase-JAR1 fusion protein. Activity was specific for JA, suggesting that covalent modification of JA is important for its function. Six other Arabidopsis genes were specifically active on indole-3-acetic acid (IAA), and one was active on both IAA and salicylic acid. These findings suggest that the JAR1 gene family is involved in multiple important plant signaling pathways.
authors.affiliation: Department of Agronomy and Horticulture, University of Nebraska, Lincoln, NE 68583, USA.
authors.forename: Paul E
authors.initials: PE
authors.lastname: Staswick
authors.forename: Iskender
authors.initials: I
authors.lastname: Tiryaki
authors.forename: Martha L
authors.initials: ML
authors.lastname: Rowe
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D017360:Arabidopsis / Q000187:drug effects / Q000201:enzymology / Q000235:genetics*; D029681:Arabidopsis Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D001517:Coleoptera; D003517:Cyclopentanes / Q000494:pharmacology*; D007210:Indoleacetic Acids / Q000494:pharmacology*; D008156:Luciferases / Q000235:genetics*; D009713:Nucleotidyltransferases / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D054883:Oxylipins; D010937:Plant Growth Regulators / Q000494:pharmacology*; D010940:Plant Proteins / Q000737:chemistry / Q000235:genetics*; D030821:Plants, Genetically Modified / Q000201:enzymology / Q000235:genetics; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis; D011994:Recombinant Proteins / Q000378:metabolism; D020156:Salicylic Acid / Q000494:pharmacology*; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D013379:Substrate Specificity; D010453:Peptide Synthases
chemical_list: D029681:Arabidopsis Proteins; D003517:Cyclopentanes; D007210:Indoleacetic Acids; D008156:Luciferases; D009713:Nucleotidyltransferases; D054883:Oxylipins; D010937:Plant Growth Regulators; D010940:Plant Proteins; D011993:Recombinant Fusion Proteins; D011994:Recombinant Proteins; D020156:Salicylic Acid; C011006:jasmonic acid; C030737:indoleacetic acid; C412831:AT2G46370 protein, Arabidopsis; D010453:Peptide Synthases