Plants employ multifaceted mechanisms to fight with numerous pathogens in nature.Resistance(R)genes are the most effective weapons against pathogen invasion since they can specifically recognize the corresponding path...Plants employ multifaceted mechanisms to fight with numerous pathogens in nature.Resistance(R)genes are the most effective weapons against pathogen invasion since they can specifically recognize the corresponding pathogen effectors or associated protein(s)to activate plant immune responses at the site of infection.Up to date,over 70 R genes have been isolated from various plant species.Most R proteins contain conserved motifs such as nucleotide-binding site(NBS),leucine-rich repeat(LRR),Toll-interleukin-1 receptor domain(TIR,homologous to cytoplasmic domains of the Drosophila Toll protein and the manamalian intefleukin-1 receptor),coiled-coil(CC)or leucine zipper(LZ)structure and protein kinase domain(PK).Recent results indicate that these domains play significant roles in R protein interactions with effector proteins from pathogens and in activating signal transduction pathways involved in innate immunity.This review highlights an overview of the recent progress in elucidating the structure,function and evolution of the isolated R genes in different plant-pathogen interaction systems.展开更多
Post-translational modification is central to protein stability and to the modulation of protein activity. Various types of protein modification, such as phosphorylation, methylation, acetylation, myristoylation, glyc...Post-translational modification is central to protein stability and to the modulation of protein activity. Various types of protein modification, such as phosphorylation, methylation, acetylation, myristoylation, glycosylation, and ubiquitination, have been reported. Among them, ubiquitination distinguishes itself from others in that most of the ubiquitinated proteins are targeted to the 26S proteasome for degradation. The ubiquitin/26S proteasome system constitutes the major protein degradation pathway in the cell. In recent years, the importance of the ubiquitination machinery in the control of numerous eukaryotic cellular functions has been increasingly appreciated. Increasing number of E3 ubiquitin ligases and their substrates, including a variety of essential cellular regulators have been identified. Studies in the past several years have revealed that the ubiquitination system is important for a broad range of plant developmental processes and responses to abiotic and biotic stresses. This review discusses recent advances in the functional analysis of ubiquitination-associated proteins from plants and pathogens that play important roles in plant-microbe interactions.展开更多
Rice diseases caused by fungi, bacteria and viruses are one of the major constraints for sustainable rice （Oryza sativa L.） production worldwide. The use of resistant cultivars is considered the most economical and ...Rice diseases caused by fungi, bacteria and viruses are one of the major constraints for sustainable rice （Oryza sativa L.） production worldwide. The use of resistant cultivars is considered the most economical and effective method to control rice diseases. In the last decade, a dozen resistance genes against the fungal pathogen Magnaporthe grisea and the bacterial pathogen Xanthomonas oryzae pv. oryzae have been cloned. Approximately half of them encode nuclear binding site （NBS） and leucine rich repeat （LRR）-containing proteins, the most common type of cloned plant resistance genes. Interestingly, four of them encode novel proteins which have not been identified in other plant species, suggesting that unique mechanisms might be involved in rice defense responses. This review summarizes the recent advances in cloning and characterization of disease resistance genes in rice and presents future perspectives for in-depth molecular analysis of the function and evolution of rice resistance genes and their interaction with avirulence genes in pathogens.展开更多
Jasmonates （JAs） are a class of plant hormones that play important roles in the regulation of plant development and plant defense. It has been shown that Arabidopsis plants produce much higher levels of anthocyanins...Jasmonates （JAs） are a class of plant hormones that play important roles in the regulation of plant development and plant defense. It has been shown that Arabidopsis plants produce much higher levels of anthocyanins when treated exogenously with methyl jasmonate （MeJA）. However, a molecular link between the JA response and anthocyanin production has not been determined. The CORONATINE INSENTITIVE1 （COI1） gene is a key player in the regulation of many JA-related responses. In the present study, we demonstrate that the COI1 gene is also required for the JA-induced accumulation of anthocyanins in Arabidopsis. Furthermore, the MeJA-inducible expression of DIHYDROFLAVONOL REDUCTASE （DFR）, an essential component in the anthocyanin biosynthesis pathway, was completely eliminated in the coil mutant. Jasmonateinduced anthocyanin accumulation was found to be independent of auxin signaling. The present results indicate that the expression of both COI1 and DFR genes is required for the regulation of JA-induced anthocyanin accumulation and that DFR may be a key downstream regulator for this process.展开更多
Many plant mltogen-actlvated protein klnases （MAPKs） play an important role In regulating responses to both ablotlc and biotic stresses. The first reported rice MAPK gene BWMK1 Is Induced by both rice blast （Magnap...Many plant mltogen-actlvated protein klnases （MAPKs） play an important role In regulating responses to both ablotlc and biotic stresses. The first reported rice MAPK gene BWMK1 Is Induced by both rice blast （Magnaporthe grisea） Infection and mechanical wounding. For further analysis of Its response to other environmental cues and plant hormones, such as jasmonlc acid （JA）, salicylic acid （SA）, and benzothladlazole （BTH）, the promoter of BWMKf was fused with the coding region of the β-glucuronldase （GUS） reporter gene. Two promoter-GUS constructs with a 1.0- and 2.5-kb promoter fragment, respectively, were generated and transformed into the Japonica rice cultIvars TP309 and Zhonghua 11. Expression of GUS was Induced in the transgenic lines by cold, drought, dark, and JA. However, light, SA, and BTH treatments suppressed GUS expression. These results demonstrate that BWMK1 Is responsive to multiple ablotlc stresses and plant hormones and may play a role In cross-talk between different signaling pathways.展开更多
基金This work was supported by grants from the Natural Science Foundation of China(No.30470990,No.30571063)the"948"Project from the Minister of Agriculture in China,the"973"Project from the Minister of Science and Technology(No.2006CB101904)+1 种基金Hunan Natural Science Foundation(No.06JJ10006)Scientific Research Fund of Hunan Provincial Education department(No.04A024).
文摘Plants employ multifaceted mechanisms to fight with numerous pathogens in nature.Resistance(R)genes are the most effective weapons against pathogen invasion since they can specifically recognize the corresponding pathogen effectors or associated protein(s)to activate plant immune responses at the site of infection.Up to date,over 70 R genes have been isolated from various plant species.Most R proteins contain conserved motifs such as nucleotide-binding site(NBS),leucine-rich repeat(LRR),Toll-interleukin-1 receptor domain(TIR,homologous to cytoplasmic domains of the Drosophila Toll protein and the manamalian intefleukin-1 receptor),coiled-coil(CC)or leucine zipper(LZ)structure and protein kinase domain(PK).Recent results indicate that these domains play significant roles in R protein interactions with effector proteins from pathogens and in activating signal transduction pathways involved in innate immunity.This review highlights an overview of the recent progress in elucidating the structure,function and evolution of the isolated R genes in different plant-pathogen interaction systems.
文摘Post-translational modification is central to protein stability and to the modulation of protein activity. Various types of protein modification, such as phosphorylation, methylation, acetylation, myristoylation, glycosylation, and ubiquitination, have been reported. Among them, ubiquitination distinguishes itself from others in that most of the ubiquitinated proteins are targeted to the 26S proteasome for degradation. The ubiquitin/26S proteasome system constitutes the major protein degradation pathway in the cell. In recent years, the importance of the ubiquitination machinery in the control of numerous eukaryotic cellular functions has been increasingly appreciated. Increasing number of E3 ubiquitin ligases and their substrates, including a variety of essential cellular regulators have been identified. Studies in the past several years have revealed that the ubiquitination system is important for a broad range of plant developmental processes and responses to abiotic and biotic stresses. This review discusses recent advances in the functional analysis of ubiquitination-associated proteins from plants and pathogens that play important roles in plant-microbe interactions.
基金Supported by the National Natural Science Foundation of China （30470990 and 30571063）, the High-Tech Research and Development （863） Program of China （2005AA241010）, the National ＂948＂ Project from the Ministry of Agriculture and the Fu-Rong Scholar Program. Publication of this paper is supported by the National Natural Science Foundation of China （30624808） and Science Publication Foundation of the Chinese Academy of Sciences.
文摘Rice diseases caused by fungi, bacteria and viruses are one of the major constraints for sustainable rice （Oryza sativa L.） production worldwide. The use of resistant cultivars is considered the most economical and effective method to control rice diseases. In the last decade, a dozen resistance genes against the fungal pathogen Magnaporthe grisea and the bacterial pathogen Xanthomonas oryzae pv. oryzae have been cloned. Approximately half of them encode nuclear binding site （NBS） and leucine rich repeat （LRR）-containing proteins, the most common type of cloned plant resistance genes. Interestingly, four of them encode novel proteins which have not been identified in other plant species, suggesting that unique mechanisms might be involved in rice defense responses. This review summarizes the recent advances in cloning and characterization of disease resistance genes in rice and presents future perspectives for in-depth molecular analysis of the function and evolution of rice resistance genes and their interaction with avirulence genes in pathogens.
基金Supported by the Hunan Provincial Natural Science Foundation of China （99jjy20016） the National Natural Science Foundation of China （30470990） the Fu-Rong Scholar Program of Hunan Provincial Govemment and Hunan Agricultural University and Scientific Research Fund of Hunan Provincial Education Department （04A024）.
文摘Jasmonates （JAs） are a class of plant hormones that play important roles in the regulation of plant development and plant defense. It has been shown that Arabidopsis plants produce much higher levels of anthocyanins when treated exogenously with methyl jasmonate （MeJA）. However, a molecular link between the JA response and anthocyanin production has not been determined. The CORONATINE INSENTITIVE1 （COI1） gene is a key player in the regulation of many JA-related responses. In the present study, we demonstrate that the COI1 gene is also required for the JA-induced accumulation of anthocyanins in Arabidopsis. Furthermore, the MeJA-inducible expression of DIHYDROFLAVONOL REDUCTASE （DFR）, an essential component in the anthocyanin biosynthesis pathway, was completely eliminated in the coil mutant. Jasmonateinduced anthocyanin accumulation was found to be independent of auxin signaling. The present results indicate that the expression of both COI1 and DFR genes is required for the regulation of JA-induced anthocyanin accumulation and that DFR may be a key downstream regulator for this process.
基金Supported, in part, by a Start-up Fund from the 0hio Agricultural Research and Development Center and the 0hio State University, the National Natural Science Foundation of China （30470990）, and Scientific Research Fund of Hunan Provincial Education Department （04A024）. Publication of this paper is supported by the National Natural Science Foundation of China （30624808）.Acknowledgements The authors thank Drs Megan Griffith at Latrobe University in Australia and Beth Hazen at American Journal of Botany for suggestions and help with the preparation of the manuscript, and Maria Billizzi for technical assistance.
文摘Many plant mltogen-actlvated protein klnases （MAPKs） play an important role In regulating responses to both ablotlc and biotic stresses. The first reported rice MAPK gene BWMK1 Is Induced by both rice blast （Magnaporthe grisea） Infection and mechanical wounding. For further analysis of Its response to other environmental cues and plant hormones, such as jasmonlc acid （JA）, salicylic acid （SA）, and benzothladlazole （BTH）, the promoter of BWMKf was fused with the coding region of the β-glucuronldase （GUS） reporter gene. Two promoter-GUS constructs with a 1.0- and 2.5-kb promoter fragment, respectively, were generated and transformed into the Japonica rice cultIvars TP309 and Zhonghua 11. Expression of GUS was Induced in the transgenic lines by cold, drought, dark, and JA. However, light, SA, and BTH treatments suppressed GUS expression. These results demonstrate that BWMK1 Is responsive to multiple ablotlc stresses and plant hormones and may play a role In cross-talk between different signaling pathways.
