title: An E3 Ligase Affects the NLR Receptor Stability and Immunity to Powdery Mildew.
abstract: Following the detection of pathogen cognate effectors, plant Nod-like receptors (NLRs) trigger isolate-specific immunity that is generally associated with cell death. The regulation of NLR stability is important to ensure effective immunity. In barley (Hordeum vulgare), the allelic Mildew locus A (MLA) receptors mediate isolate-specific disease resistance against powdery mildew fungus (Blumeria graminis f. sp. hordei). Currently, how MLA stability is controlled remains unknown. Here, we identified an MLA-interacting RING-type E3 ligase, MIR1, that interacts with several MLAs. We showed that the carboxyl-terminal TPR domain of MIR1 mediates the interaction with the coiled-coil domain-containing region of functional MLAs, such as MLA1, MLA6, and MLA10, but not with that of the nonfunctional MLA18-1. MIR1 can ubiquitinate the amino-terminal region of MLAs in vitro and promotes the proteasomal degradation of MLAs in vitro and in planta. Both proteasome inhibitor treatment and virus-induced gene silencing-mediated MIR1 silencing significantly increased MLA abundance in barley transgenic lines. Furthermore, overexpression of MIR1 specifically compromised MLA-mediated disease resistance in barley, while coexpression of MIR1 and MLA10 attenuated MLA10-induced cell death signaling in Nicotiana benthamiana Together, our data reveal a mechanism for the control of the stability of MLA immune receptors and for the attenuation of MLA-triggered defense signaling by a RING-type E3 ligase via the ubiquitin proteasome system.
authors: State Key Laboratory of Plant Cell and Chromosome Engineering (T.W., C.C., C.G., Q.-H.S.) and State Key Laboratory of Plant Genomics, Institute of Genetics and Developmental Biology (S.T., Q.X.), Chinese Academy of Sciences, Beijing 100101, China.
authors: Tao
authors: 0000-0001-5593-7472
authors: T
authors: Wang
authors: State Key Laboratory of Plant Cell and Chromosome Engineering (T.W., C.C., C.G., Q.-H.S.) and State Key Laboratory of Plant Genomics, Institute of Genetics and Developmental Biology (S.T., Q.X.), Chinese Academy of Sciences, Beijing 100101, China.
authors: Cheng
authors: C
authors: Chang
authors: State Key Laboratory of Plant Cell and Chromosome Engineering (T.W., C.C., C.G., Q.-H.S.) and State Key Laboratory of Plant Genomics, Institute of Genetics and Developmental Biology (S.T., Q.X.), Chinese Academy of Sciences, Beijing 100101, China.
authors: Cheng
authors: C
authors: Gu
authors: State Key Laboratory of Plant Cell and Chromosome Engineering (T.W., C.C., C.G., Q.-H.S.) and State Key Laboratory of Plant Genomics, Institute of Genetics and Developmental Biology (S.T., Q.X.), Chinese Academy of Sciences, Beijing 100101, China.
authors: Sanyuan
authors: S
authors: Tang
authors: State Key Laboratory of Plant Cell and Chromosome Engineering (T.W., C.C., C.G., Q.-H.S.) and State Key Laboratory of Plant Genomics, Institute of Genetics and Developmental Biology (S.T., Q.X.), Chinese Academy of Sciences, Beijing 100101, China.
authors: Qi
authors: 0000-0002-8262-9093
authors: Q
authors: Xie
authors: State Key Laboratory of Plant Cell and Chromosome Engineering (T.W., C.C., C.G., Q.-H.S.) and State Key Laboratory of Plant Genomics, Institute of Genetics and Developmental Biology (S.T., Q.X.), Chinese Academy of Sciences, Beijing 100101, China qhshen@genetics.ac.cn.
authors: Qian-Hua
authors: 0000-0002-9446-3086
authors: QH
authors: Shen
mesh_terms: D001203:Ascomycota / Q000502:physiology*; D016923:Cell Death; D060467:Disease Resistance; D056426:Genetic Loci; D001467:Hordeum / Q000201:enzymology* / Q000276:immunology / Q000382:microbiology*; D010935:Plant Diseases / Q000276:immunology* / Q000382:microbiology; D057865:Plant Immunity; D010940:Plant Proteins / Q000737:chemistry / Q000378:metabolism*; D030821:Plants, Genetically Modified; D046988:Proteasome Endopeptidase Complex / Q000378:metabolism; D011485:Protein Binding; D059748:Proteolysis; D044767:Ubiquitin-Protein Ligases / Q000378:metabolism*; D054875:Ubiquitination
chemical_list: D010940:Plant Proteins; D044767:Ubiquitin-Protein Ligases; D046988:Proteasome Endopeptidase Complex