Disease relevance of COI1

• Independent mutations in COI1 and GL1 led to a faster larval weight gain, but the gl1 mutation had relatively little effect on the expression of the insect-responsive genes examined [1].
• Activation of a COI1-dependent pathway in Arabidopsis by Pseudomonas syringae type III effectors and coronatine [2].

High impact information on COI1

• COI1: an Arabidopsis gene required for jasmonate-regulated defense and fertility [3].
• The predicted amino acid sequence of the COI1 protein contains 16 leucine-rich repeats and an F-box motif [3].
• The coi1 mutation defines an Arabidopsis gene required for response to jasmonates, which regulate defense against insects and pathogens, wound healing, and pollen fertility [3].
• Together, these results suggest that OCP3 is an important factor for the COI1-dependent resistance of plants to infection by necrotrophic pathogens [4].
• Conversely, antisense suppression of WRKY70 activates JA-responsive/COI1-dependent genes [5].

Biological context of COI1

• COI1(E22A), a single amino acid substitution in the F-box motif of COI1, abolishes the formation of the SCF(COI1) complexes and results in loss of the JA response [6].
• Xie and colleagues previously isolated the Arabidopsis COI1 gene that is required for response to jasmonates (JAs), which regulate root growth, pollen fertility, wound healing, and defense against insects and pathogens [6].
• Blocked JA signaling in coronatine-insensitive (coi1) and enhanced expression of SA-signaled disease resistance in hypersensitive response-like (hrl1) mutants reduced constitutive GS concentrations, while blocking SA signaling at the mediator protein npr1 mutant (NPR) increased them [7].
• We demonstrated a novel function for the riboflavin pathway that acts downstream of COI1 in the JA signaling pathway and is required for suppression of the COI1-mediated root growth, senescence, and plant defense [8].
• Genome expression profile analyses indicated that JA-triggered genome expression is critically dependent on COI1 dosage [9].

Associations of COI1 with chemical compounds

• We found increased GS accumulation in response to insect feeding, which required functional NPR1 and ETR1 but not COI1 or SA [7].
• The expression of 181 BIGs was dependent on a functional COI1 gene required for jasmonate signaling, whereas the expression of 63 and 80 BIGs were dependent on ethylene (ET) signaling or salicylic acid accumulation, respectively, based on results from ein2 and nahG plants [10].
• Mutant COI1 proteins revealed that the F-box is required for interaction with SKP1s, but that sequences in leucine-rich repeat domains are required for interaction with the histone deacetylase [11].
• These results suggest that P. syringae type III effectors and coronatine act by augmenting a COI1-dependent pathway to promote parasitism [2].
• In this study, we isolated an F-box protein gene from soybean, which shares significant homology with the Arabidopsis COI1 and similarly contains an F-box motif and leucine rich repeats (LRR), here designated GmCOI1 (Glycine max L. (Merr.) COI1) [12].

Physical interactions of COI1

• The COP9 signalosome interacts physically with SCF COI1 and modulates jasmonate responses [9].

Other interactions of COI1

• These results suggest that the COI1-mediated JA response is dependent on the SCF(COI1) complexes in Arabidopsis and that the AXR1-dependent modification of the AtCUL1 subunit of SCF(COI1) complexes is important for JA signaling [6].
• Of the 645 genes induced by A. brassicicola in wild-type and pad3 plants, 265 required COI1 for full expression [13].
• A third group of mutants comprised of eds8, pad1, ein2, and coi1 affected ethylene and jasmonate signaling [14].
• COI1 encodes an F-box protein, which is a subunit of SCF(COI1) E3 ubiquitin ligase, and is required for jasmonate (JA) responses [9].
• Ca2+ and calmodulin seem to act downstream of both JA and the COI1 gene in the JA-dependent pathway, and downstream of reversible phosphorylation events that differentially regulate JA-dependent and JA-independent wound signal transduction pathways [15].

Analytical, diagnostic and therapeutic context of COI1

• Epitope-tagged COI1 was introduced into Arabidopsis plants and cell cultures [11].
• Here, we demonstrate using coimmunoprecipitation and gel-filtration analyses that endogenous as well as epitope-tagged COI1 forms SCF(COI1) and associates directly with CSN in vivo [9].

References