Map-based cloning of plant disease resistance (R) genes is time-consuming. Here, we reported the isolation of blast R gene Pid4 using comparative transcriptomic profiling and genome-wide sequence analysis. Pid4 encode...Map-based cloning of plant disease resistance (R) genes is time-consuming. Here, we reported the isolation of blast R gene Pid4 using comparative transcriptomic profiling and genome-wide sequence analysis. Pid4 encodes a coiled-coil nucleotide-binding site leucine-rich repeat(CC-NBS-LRR) protein and is constitutively expressed at diverse developmental stages in the rice variety Digu. The Pid4 protein is localized in both the nucleus and cytoplasm. Introduction of Pid4 into susceptible rice cultivars confers race-specific resistance to leaf and neck blast. Amino acid sequence comparison and blast resistance spectrum tests showed that Pid4 is a novel R gene, different from the previously reported R genes located in the same gene cluster. A Pid4 Indel marker was developed to facilitate the identification of Pid4 in different rice varieties. We demonstrated that a plant R gene can be quickly isolated using transcriptomic profiling coupled with genome-wide sequence analysis.展开更多
The rice Xa21 gene, which confers resistance to the bacterial pathogen Xanthomonas oryzae pv. oryzae （Xoo）, encodes a receptor-like kinase, Few components involved in transducing the Xa21-mediated defense response h...The rice Xa21 gene, which confers resistance to the bacterial pathogen Xanthomonas oryzae pv. oryzae （Xoo）, encodes a receptor-like kinase, Few components involved in transducing the Xa21-mediated defense response have yet been identified. Here, we report that XA21 binds to a WRKY transcription factor, called OsWRKY62. The OsWRKY62 gene encodes two splice variants （OsWRKY62.1 and OsWRKY62.2）. OsWRKY62.1：smGFP2 and OsWRKY62.2：smGFP2 fusion pro- teins partially localize to the nucleus. Transgenic plants overexpressing OsWRKY62.1 are compromised in basal defense and Xa21-mediated resistance to Xoo. Furthermore, overexpression of OsWRKY62.1 suppresses the activation of defenserelated genes. These results imply that OsWRKY62 functions as a negative regulator of innate immunity in rice, and serves as a critical mediator of both basal and race-specific defense responses.展开更多
The rice XA21 immune receptor kinase and the structurally related XA3 receptor confer immunity to Xanthomonas oryzae pv. oryzae （Xoo）, the causal agent of bacterial leaf blight. Here we report the isolation of OsSER...The rice XA21 immune receptor kinase and the structurally related XA3 receptor confer immunity to Xanthomonas oryzae pv. oryzae （Xoo）, the causal agent of bacterial leaf blight. Here we report the isolation of OsSERK2 （rice somatic embryogenesis receptor kinase 2） and demonstrate that OsSERK2 positively regulates immunity mediated by XA21 and XA3 as well as the rice immune receptor FLS2 （OsFLS2）. Rice plants silenced for OsSerk2 display altered morphology and reduced sensitivity to the hormone brassinolide. OsSERK2 interacts with the intracellular domains of each immune receptor in the yeast two-hybrid system in a kinase activity-dependent manner. OsSERK2 undergoes bidi- rectional transphosphorylation with XA21 in vitro and forms a constitutive complex with XA21 in vivo. These results demonstrate an essential role for OsSERK2 in the function of three rice immune receptors and suggest that direct interaction with the rice immune receptors is critical for their function. Taken together, our findings suggest that the mechanism of OsSERK2-meditated regulation of rice XA21, XA3, and FLS2 differs from that of AtSERK3/BAK1-mediated regulation of Arabidopsis FLS2 and EFR.展开更多
Despite the lack of a cellular,adaptive immune system,plants share with animals an innate immune system and can effectively fight off pathogen attack using two layers of defense response:the first layer consists of pl...Despite the lack of a cellular,adaptive immune system,plants share with animals an innate immune system and can effectively fight off pathogen attack using two layers of defense response:the first layer consists of plasma membrane-localized pattern recognition receptors(PRRs)that recognize pathogen-associated molecular patterns(PAMPs)and can mount a pattern-triggered immunity(PTI);the second layer comprises cytoplasmic nucleotide-binding,leucine-rich repeats receptors(NLRs)that recognize pathogensecreted effectors and mount an effector-triggered immunity(ETI)(Shamrai,2014).Plants contain hundreds of NLR genes constituting one of the largest families of genes.Because plant NLR genes can mount the strongest immune response,often including a hypersensitive response,upon recognition of its cognate effector,they were initially characterized as resistance(R)genes and conform to the genefor-gene hypothesis postulated in 1955(Hh,1955;McHale et al.,2006).The plant NLR-mediated ETI response is thus comparable to the animal inflammatory response.展开更多
XA21 encodes a rice immune receptor that confers robust resistance to most strains of the Gram-negative bacterium Xanthomonas oryzae pv.oryzae(Xoo).XA21-mediated immunity is triggered by recognition of a small protein...XA21 encodes a rice immune receptor that confers robust resistance to most strains of the Gram-negative bacterium Xanthomonas oryzae pv.oryzae(Xoo).XA21-mediated immunity is triggered by recognition of a small protein called RaxX-sY(required for activation of XA21-mediated immunity X,tyrosine-sulfated)secreted by Xoo.To identify components regulating XA21-mediated immunity,we generated and screened a mutant population of fast-neutron-mutagenized rice expressing Ubi:Myc-XA21 for those susceptible to Xoo.Here,we report the characterization of one of these rice mutants,named sxi2(suppressor of XA21-mediated immunity-2).Whole-genome sequencing revealed that sxi2 carries a deletion of the PALADIN(PALD)gene encoding a protein with three putative protein tyrosine phosphatase-like domains(PTP-A,-B,and-C).Expression of PALD in the sxi2 genetic background was sufficient to complement the susceptible phenotype,which requires the catalytic cysteine of the PTP-A active site to restore resistance.PALD coimmunoprecipitated with the full-length XA21 protein,whose levels are positively regulated by the presence of the PALD transgene.Furthermore,we foundd that sxi2 retains many hallmarks of XA21-mediated immunity,similar to the wild type.These results reveal that PALD,a previously uncharacterized class of phosphatase,functions in rice innate immunity,and suggest that the conserved cysteine in the PTP-A domain of PALD is required for its immune function.展开更多
Dear Editor, Xylan polysaccharides constitute the major non-cellulosic components in secondary cell walls of dicots and in both primary and secondary cell walls of grasses （Scheller and Ulvskov, 2010）. Xylan is com...Dear Editor, Xylan polysaccharides constitute the major non-cellulosic components in secondary cell walls of dicots and in both primary and secondary cell walls of grasses （Scheller and Ulvskov, 2010）. Xylan is composed of a linear backbone of 13（1-4）-linked xylose （Xyl）. In grasses, the xylan backbone is substituted with 03-1inked and 02-1inked arabinose residues and, to a lesser extent, a（1-3）-Iinked glucuronic acid residues.展开更多
基金supported by the National Key Research and Development Program of China (2016YFD0100600)the Transgenic Projects from the Chinese Ministry of Agriculture (2014ZX0800903B)+12 种基金supported by the Transgenic Projects from the Chinese Ministry of Agriculture (2016ZX08001002)the National Natural Science Foundation of China (31571994 and 31772153)supported by the National Natural Science Foundation of China (31772152)supported by the National Natural Science Foundation of China (31701779)supported by the National Natural Science Foundation of China (31601290)the Program for New Century Excellent Talents in University from the Ministry of Education in Chinathe “Hundred Talents Plan” Foundationthe Youth Foundation (13QNJJ0076)supported by NSF PGRP IOS 1237975NIH GM59962USDA NIFA 2017-6701326590the Open Research Fund of State Key Laboratory of Hybrid Rice (Hunan Hybrid Rice Research Center) (2017KF01)the project funded by China Postdoctoral Science Foundation (2017M612984)
文摘Map-based cloning of plant disease resistance (R) genes is time-consuming. Here, we reported the isolation of blast R gene Pid4 using comparative transcriptomic profiling and genome-wide sequence analysis. Pid4 encodes a coiled-coil nucleotide-binding site leucine-rich repeat(CC-NBS-LRR) protein and is constitutively expressed at diverse developmental stages in the rice variety Digu. The Pid4 protein is localized in both the nucleus and cytoplasm. Introduction of Pid4 into susceptible rice cultivars confers race-specific resistance to leaf and neck blast. Amino acid sequence comparison and blast resistance spectrum tests showed that Pid4 is a novel R gene, different from the previously reported R genes located in the same gene cluster. A Pid4 Indel marker was developed to facilitate the identification of Pid4 in different rice varieties. We demonstrated that a plant R gene can be quickly isolated using transcriptomic profiling coupled with genome-wide sequence analysis.
文摘The rice Xa21 gene, which confers resistance to the bacterial pathogen Xanthomonas oryzae pv. oryzae （Xoo）, encodes a receptor-like kinase, Few components involved in transducing the Xa21-mediated defense response have yet been identified. Here, we report that XA21 binds to a WRKY transcription factor, called OsWRKY62. The OsWRKY62 gene encodes two splice variants （OsWRKY62.1 and OsWRKY62.2）. OsWRKY62.1：smGFP2 and OsWRKY62.2：smGFP2 fusion pro- teins partially localize to the nucleus. Transgenic plants overexpressing OsWRKY62.1 are compromised in basal defense and Xa21-mediated resistance to Xoo. Furthermore, overexpression of OsWRKY62.1 suppresses the activation of defenserelated genes. These results imply that OsWRKY62 functions as a negative regulator of innate immunity in rice, and serves as a critical mediator of both basal and race-specific defense responses.
文摘The rice XA21 immune receptor kinase and the structurally related XA3 receptor confer immunity to Xanthomonas oryzae pv. oryzae （Xoo）, the causal agent of bacterial leaf blight. Here we report the isolation of OsSERK2 （rice somatic embryogenesis receptor kinase 2） and demonstrate that OsSERK2 positively regulates immunity mediated by XA21 and XA3 as well as the rice immune receptor FLS2 （OsFLS2）. Rice plants silenced for OsSerk2 display altered morphology and reduced sensitivity to the hormone brassinolide. OsSERK2 interacts with the intracellular domains of each immune receptor in the yeast two-hybrid system in a kinase activity-dependent manner. OsSERK2 undergoes bidi- rectional transphosphorylation with XA21 in vitro and forms a constitutive complex with XA21 in vivo. These results demonstrate an essential role for OsSERK2 in the function of three rice immune receptors and suggest that direct interaction with the rice immune receptors is critical for their function. Taken together, our findings suggest that the mechanism of OsSERK2-meditated regulation of rice XA21, XA3, and FLS2 differs from that of AtSERK3/BAK1-mediated regulation of Arabidopsis FLS2 and EFR.
文摘Despite the lack of a cellular,adaptive immune system,plants share with animals an innate immune system and can effectively fight off pathogen attack using two layers of defense response:the first layer consists of plasma membrane-localized pattern recognition receptors(PRRs)that recognize pathogen-associated molecular patterns(PAMPs)and can mount a pattern-triggered immunity(PTI);the second layer comprises cytoplasmic nucleotide-binding,leucine-rich repeats receptors(NLRs)that recognize pathogensecreted effectors and mount an effector-triggered immunity(ETI)(Shamrai,2014).Plants contain hundreds of NLR genes constituting one of the largest families of genes.Because plant NLR genes can mount the strongest immune response,often including a hypersensitive response,upon recognition of its cognate effector,they were initially characterized as resistance(R)genes and conform to the genefor-gene hypothesis postulated in 1955(Hh,1955;McHale et al.,2006).The plant NLR-mediated ETI response is thus comparable to the animal inflammatory response.
基金supported by the following grants to P.R.:NIH no.GM59962,NIH no.GM122968,NSF no.1237975,NSF IOS-1656501,and NSF-NIFA no.2017-03128supported by the following grant to T.-C.C.:a Taiwan Government Scholarship.Support for M.S.+1 种基金provided by the Corteva Open Innovations Programsupported by the Office of Science,Office of Biological and Environmental Research of the U.S.Department of Energy under contract no.DE-AC02-05CH11231.
文摘XA21 encodes a rice immune receptor that confers robust resistance to most strains of the Gram-negative bacterium Xanthomonas oryzae pv.oryzae(Xoo).XA21-mediated immunity is triggered by recognition of a small protein called RaxX-sY(required for activation of XA21-mediated immunity X,tyrosine-sulfated)secreted by Xoo.To identify components regulating XA21-mediated immunity,we generated and screened a mutant population of fast-neutron-mutagenized rice expressing Ubi:Myc-XA21 for those susceptible to Xoo.Here,we report the characterization of one of these rice mutants,named sxi2(suppressor of XA21-mediated immunity-2).Whole-genome sequencing revealed that sxi2 carries a deletion of the PALADIN(PALD)gene encoding a protein with three putative protein tyrosine phosphatase-like domains(PTP-A,-B,and-C).Expression of PALD in the sxi2 genetic background was sufficient to complement the susceptible phenotype,which requires the catalytic cysteine of the PTP-A active site to restore resistance.PALD coimmunoprecipitated with the full-length XA21 protein,whose levels are positively regulated by the presence of the PALD transgene.Furthermore,we foundd that sxi2 retains many hallmarks of XA21-mediated immunity,similar to the wild type.These results reveal that PALD,a previously uncharacterized class of phosphatase,functions in rice innate immunity,and suggest that the conserved cysteine in the PTP-A domain of PALD is required for its immune function.
文摘Dear Editor, Xylan polysaccharides constitute the major non-cellulosic components in secondary cell walls of dicots and in both primary and secondary cell walls of grasses （Scheller and Ulvskov, 2010）. Xylan is composed of a linear backbone of 13（1-4）-linked xylose （Xyl）. In grasses, the xylan backbone is substituted with 03-1inked and 02-1inked arabinose residues and, to a lesser extent, a（1-3）-Iinked glucuronic acid residues.
