title: CEBiP is the major chitin oligomer-binding protein in rice and plays a main role in the perception of chitin oligomers.
abstract: CEBiP, a plasma membrane-localized glycoprotein of rice, directly binds with chitin elicitors (CE), and has been identified as a receptor for CE by using CEBiP-RNAi rice cells. To further clarify the function of CEBiP, we produced CEBiP-disrupted rice plants by applying an efficient Agrobacterium-mediated gene-targeting system based on homologous recombination, which has recently been developed for rice. Homologous recombination occurred at the CEBiP locus in ~0.5 % of the positive/negative selected calli. In the self-pollinated next generation, it was confirmed that the first exon of CEBiP was replaced with the hygromycin selection cassette as designed, and that the expression of CEBiP was completely deficient in homozygous cebip lines. Affinity-labeling analysis using biotinylated N-acetylchitooctaose demonstrated that CEBiP is the major CE-binding protein in rice cultured cells and leaves, which was consistent with the result that the response to CE in cebip cells was greatly diminished. Nevertheless, we observed a significant decrease in disease resistance against Magnaporthe oryzae, the causal agent of rice blast disease, only when the cebip leaf sheaths were inoculated with a weakly virulent strain, suggesting that CE perception during the infection process of M. oryzae is limited. The response to peptidoglycan and lipopolysaccharides in cebip cells was not affected, strongly suggesting that CEBiP is a CE-specific receptor.
authors.affiliation: Genetically Modified Organism Research Center, National Institute of Agrobiological Sciences, Tsukuba, Ibaraki, 305-8602, Japan.
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Kouzai
authors.forename: Keisuke
authors.initials: K
authors.lastname: Nakajima
authors.forename: Masahiro
authors.initials: M
authors.lastname: Hayafune
authors.forename: Kenjirou
authors.initials: K
authors.lastname: Ozawa
authors.forename: Hanae
authors.initials: H
authors.lastname: Kaku
authors.forename: Naoto
authors.initials: N
authors.lastname: Shibuya
authors.forename: Eiichi
authors.initials: E
authors.lastname: Minami
authors.forename: Yoko
authors.initials: Y
authors.lastname: Nishizawa
mesh_terms: D001483:Base Sequence; D002686:Chitin / Q000378:metabolism*; D004591:Electrophoresis, Polyacrylamide Gel; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D005816:Genetic Complementation Test; D054884:Host-Pathogen Interactions; D006861:Hydrogen Peroxide / Q000378:metabolism; D020082:Magnaporthe / Q000502:physiology; D009154:Mutation; D009844:Oligosaccharides / Q000378:metabolism / Q000494:pharmacology; D012275:Oryza / Q000235:genetics / Q000378:metabolism* / Q000382:microbiology; D010457:Peptidoglycan / Q000378:metabolism; D010935:Plant Diseases / Q000235:genetics / Q000382:microbiology; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism*; D030821:Plants, Genetically Modified; D011485:Protein Binding; D034622:RNA Interference; D051192:Receptors, Pattern Recognition / Q000235:genetics / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: C514377:N-acetylchitoheptaose; D009844:Oligosaccharides; D010457:Peptidoglycan; D010940:Plant Proteins; D051192:Receptors, Pattern Recognition; D002686:Chitin; D006861:Hydrogen Peroxide