title: Oryza sativa COI homologues restore jasmonate signal transduction in Arabidopsis coi1-1 mutants.
abstract: CORONATINE INSENSITIVE 1 (COI1) encodes an E3 ubiquitin ligase complex component that interacts with JAZ proteins and targets them for degradation in response to JA signaling. The Arabidopsis genome has a single copy of COI1, but the Oryza sativa genome has three closely related COI homologs. To examine the functions of the three OsCOIs, we used yeast two-hybrid assays to examine their interactions with JAZ proteins and found that OsCOIs interacted with OsJAZs and with JAZs, in a coronatine dependent manner. We also tested whether OsCOI1a and OsCOI1b could complement Arabidopsis coi1-1 mutants and found that overexpression of either gene in the coi1-1 mutant resulted in restoration of JA signal transduction and production of seeds, indicating successful complementation. Although OsCOI2 interacted with a few OsJAZs, we were not able to successfully complement the coi1-1 mutant with OsCOI2. Molecular modeling revealed that the three OsCOIs adopt 3D structures similar to COI1. Structural differences resulting from amino acid variations, especially among amino acid residues involved in the interaction with coronatine and JAZ proteins, were tested by mutation analysis. When His-391 in OsCOI2 was substituted with Tyr-391, OsCOI2 interacted with a wider range of JAZ proteins, including OsJAZ1, 2, 5∼9 and 11, and complemented coi1-1 mutants at a higher frequency than the other OsCOIs and COI1. These results indicate that the three OsCOIs are orthologues of COI1 and play key roles in JA signaling.
authors: Department of Agricultural Biotechnology, Seoul National University, Seoul, Korea.
authors: Han Yong
authors: HY
authors: Lee
authors: Ju-Seok
authors: JS
authors: Seo
authors: Jang Hee
authors: JH
authors: Cho
authors: Harin
authors: H
authors: Jung
authors: Ju-Kon
authors: JK
authors: Kim
authors: Jong Seob
authors: JS
authors: Lee
authors: Sangkee
authors: S
authors: Rhee
authors: Yang
authors: Y
authors: Do Choi
mesh_terms: D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000235:genetics* / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D003517:Cyclopentanes / Q000737:chemistry* / Q000378:metabolism; D018506:Gene Expression Regulation, Plant; D005816:Genetic Complementation Test; D018745:Genome, Plant; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009154:Mutation; D012275:Oryza / Q000235:genetics* / Q000502:physiology; D054883:Oxylipins / Q000737:chemistry* / Q000378:metabolism; D010940:Plant Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D030821:Plants, Genetically Modified; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D015398:Signal Transduction / Q000235:genetics*; D020798:Two-Hybrid System Techniques; D044767:Ubiquitin-Protein Ligases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism
chemical_list: D029681:Arabidopsis Proteins; C112279:COI1 protein, Arabidopsis; D003517:Cyclopentanes; D054883:Oxylipins; D010940:Plant Proteins; D011994:Recombinant Proteins; C011006:jasmonic acid; D044767:Ubiquitin-Protein Ligases