Ligase Clades

Clade I – LACS

Much of our work on these genes has been published.

  • At2g47240
  • At1g49430
  • At1g64400
  • At4g23850
  • At4g11030
  • At3g05970
  • At5g27600
  • At2g04350
  • At1g77590
  • At4g14070
  • At3g23790

Clade II

The members of this clade are under active investigation by our laboratory, using the research approaches described.

  • At5g36880
  • At5g23050
  • At1g55320

Clade III

The characterization of JAR1 by Staswick et al. revealed that the 19 genes in clade III are not CoA ligases.

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.

Staswick PE, Tiryaki I, and Rowe ML

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.

Clade IV 4 CL genes

Ehlting, J, Buttner, D, Wang, Q, Douglas, CJ, Somssich, IE, and Kombrink, E. 1999. Three 4-coumarate:coenzyme A ligases in Arabidopsis thaliana represent two evolutionarily divergent classes in angiosperms.  Plant J. 19(1):9-20.

Schneider, K, Hovel, K, Witzel, K, Hamberger, B, Schomburg, D, Kombrink, E, and Stuible, HP. 2003. The substrate specificity-determining amino acid code of 4-coumarate:CoA ligase. Proc. Natl. Acad. Sci. USA. 100(14):8601-8606.

  • At1g51680
  • At3g21240
  • At1g65060
  • At3g21230
  • At1g62940

Clade V “4CL-like”

At4g05160, At5g63380 activities reported:  At4g05160 has activity with with medium-chain fatty acids, medium-chain fatty acids carrying a phenyl substitution, long-chain fatty acids, as well as the jasmonic acid precursors 12-oxo-phytodienoic acid and 3-oxo-2-(2′-pentenyl)-cyclopentane-1-hexanoic acid.

At5g63380, showed high activity with long-chain fatty acids and 12-oxo-phytodienoic acid, the latter representing the most efficiently converted substrate.

Schneider, K, Kienow, L, Schmelzer, E, Colby, T, Bartsch, M, Miersch, O, Wasternack, C, Kombrink, E, and Stuible, HP.  2005. A new type of peroxisomal acyl-coenzyme A synthetase from Arabidopsis thaliana has the catalytic capacity to activate biosynthetic precursors of jasmonic acid.  J. Biol. Chem. 280(14):13962-13972. Epub 2005 Jan 26.

  • At1g20500
  • At1g20490
  • At5g38120
  • At1g20510
  • At1g20480
  • At5g63380
  • At4g05160
  • At4g19010

Clade VI

The members of this clade are under active investigation by our laboaratory, using the research approaches described.

  • At1g20560
  • At2g17650
  • At1g77240
  • At5g16370
  • At5g16340
  • At3g16910
  • At1g75960
  • At1g21540
  • At1g21530
  • At1g66120
  • At1g65890
  • At1g65880
  • At1g68270
  • At1g76290

Clade VII

The members of this clade are under active investigation by our laboratory, using the research approaches described.

  • At3g48990
  • At3g16170
  • At1g30520