Diverse bacterial and fungal pathogens attack plants,causing biotic stress and severe yield losses globally.These losses are expected to become more serious as climate change improves conditions for many pathogens.The...Diverse bacterial and fungal pathogens attack plants,causing biotic stress and severe yield losses globally.These losses are expected to become more serious as climate change improves conditions for many pathogens.Therefore,identifying genes conferring broad-spectrum disease resistance and elucidating their underlying mechanisms provides important resources for plant breeding.WRKY transcription factors affect plant growth and stress responses.However,the functions of many WRKY proteins remain to be elucidated.Here,we demonstrated the role of rice(Oryza sativa)WRKY groupⅢtranscription factor OsWRKY65 in immunity.OsWRKY65 localized to the nucleus and acted as transcriptional repressor.Genetic and molecular functional analyses showed that OsWRKY65 increases resistance to the fungal pathogen Fusarium fujikuroi through downregulation of GA signaling and upregulation of JA signaling.Moreover,OsWRKY65 modulated the expression of the key genes that confer susceptibility or resistance to Xanthomonas oryzae pv.oryzae to enhance immunity against the pathogen.In particular,OsWRKY65directly bound to the promoter region of OsSWEET13 and repressed its expression.Taken together,our findings demonstrate that the OsWRKY65 enhances resistance to fungal and bacterial pathogens in rice.展开更多
WRKY family proteins are a class of plant specific transcription factors that involve in many stress response pathways. It has been shown that one Arabidopsis WRKY protein, AtWRKY29/22, is activated by MAP kinase sign...WRKY family proteins are a class of plant specific transcription factors that involve in many stress response pathways. It has been shown that one Arabidopsis WRKY protein, AtWRKY29/22, is activated by MAP kinase signaling cascade and confers resistance to both bacterial and fungal pathogens. However, little is known about the biological roles of WRKY proteins in rice. In this study, we investigated the expression patterns of rice AtWRKY29/22 homolog, OsWRKY03, under different conditions, and also its possible role involved in plant defense. Our results showed that OsWRKY03 was up-regulated by several defense signaling molecules or different treatments. Further analysis revealed that the expres- sion of OsWRKY03 was light dependent. Transcriptional activation activity of OsWRKY03 was also demonstrated by yeast functional assay. Transient expression of OsWRKY03-GFP fusion protein in onion epidermis cells showed that OsWRKY03 was a nuclear localized protein. OsNPR1 as well as several other pathogenesis-related genes, such as OsPR1b, phenylalanine ammonia-lyase (ZB8) and peroxidase (POX22.3), were induced in OsWRKY03-overexpressing transgenic plants. These results indicated that OsWRKY03 is located upstream of OsNPR1 as a transcriptional activator in salicylic acid (SA)-dependent or jasmonic acid (JA)-dependent defense signaling cascades.展开更多
OsPRIOa is one of the well known pathogenesis-related genes in rice,and is induced by multiple plant hormones and pathogens.However,the underlying transcriptional regulation mechanisms in response to differe nt signal...OsPRIOa is one of the well known pathogenesis-related genes in rice,and is induced by multiple plant hormones and pathogens.However,the underlying transcriptional regulation mechanisms in response to differe nt signals and their crosstalks are still largely unknown.In order to find new players participated in the activation of OsPRIOa,we systematically analyzed the basal expression patterns as well as the expression responses of a 2.5 kb OsPRIOa promoter in rice transgenic plants after phytohormone and pathogen stimulations.In agreement with the native gene expression,the OsPRIOa promoter can drive glucuronidase(GUS)gene expressing in spots of leaf cells,leaf trichomes,lemmas and paleae,germinating embryos,calli and root tips.The leaf expression of OsPR10a::GUS was dramatically in creased upon jasm onic acid(JA)and cytoki nin(CK)treatme nts,or challe nges of the pathogen Magnaporthe grisea and Xanthomonas oryzae pv.oryzae.Thus,the OsPRIOa promoter reported here can faithfully reflect its native gene expression.The effects of several JA and CK responsive OsWRKY genes on the regulation of OsPRIOa promoter were then inspected by luciferase transient expression assay,and the JA inducible OsWRKYlO transcription factor was found as a new positive regulator of OsPRIOa.However,the key transcription factors of JA and CK signaling pathways,OsMYC2 and B-type response regulators,were not responsible for the activation of OsPRIOa promote Our findings provided new in sights into the regulation of OsPRIOa expression during plan t-hormone/pathoge n interactions,and the OsPRIOa reporter system can be useful to unravel novel regulators from both pathogen and host.展开更多
Plant WRKY transcription factors （TFs） constitute one of the largest families of proteinsinvolved in biotic and abiotic stress responses. These TFs have a conserved 60 amino acid WRKYdomain at the N-terminal and a z...Plant WRKY transcription factors （TFs） constitute one of the largest families of proteinsinvolved in biotic and abiotic stress responses. These TFs have a conserved 60 amino acid WRKYdomain at the N-terminal and a zinc finger motif at the C-terminal. To examine the relevance ofOsWRKY72 in imparting salinity stress tolerance, two indica rice genotypes, Rasi （tolerant genotype）and Tellahamsa （susceptible genotype）, were used. In Rasi seedlings at 12 h under 100 mmol/L NaClstress, OsWRKY72 expression was up-regulated, whereas in Tellahamsa, it was highly up-regulated atlethal stress. Full-length OsWRKY72 cDNA was cloned from these two rice genotypes for furtheranalysis. We identified a variant, termed as OsWRKY72b that carries an additional sequence of 111 bpwithin the WRKY domain. Expression of OsWRKY72b was higher under salinity stress in Rasi than inTellahamsa. Disorder prediction of OsWRKY72b showed that the additional sequence in the WRKYdomain is ordered thereby maintaining the tertiary structure that might interact with the major groove ofDNA. Prediction of phosphorylation sites in OsWRKY72b indicated that a few serine residues could bethe potential phosphorylation sites. In this study, we firstly reported a OsWRKY72 variant that couldhave a role in abiotic stress responses.展开更多
基金funded by Research Program for Agricultural Science and Technology Development(PJ01570601)and the Fellowship Program(PJ01661001 and PJ01570601)of the National Institute of Agricultural Sciences,Rural Development Administration,Republic of Korea。
文摘Diverse bacterial and fungal pathogens attack plants,causing biotic stress and severe yield losses globally.These losses are expected to become more serious as climate change improves conditions for many pathogens.Therefore,identifying genes conferring broad-spectrum disease resistance and elucidating their underlying mechanisms provides important resources for plant breeding.WRKY transcription factors affect plant growth and stress responses.However,the functions of many WRKY proteins remain to be elucidated.Here,we demonstrated the role of rice(Oryza sativa)WRKY groupⅢtranscription factor OsWRKY65 in immunity.OsWRKY65 localized to the nucleus and acted as transcriptional repressor.Genetic and molecular functional analyses showed that OsWRKY65 increases resistance to the fungal pathogen Fusarium fujikuroi through downregulation of GA signaling and upregulation of JA signaling.Moreover,OsWRKY65 modulated the expression of the key genes that confer susceptibility or resistance to Xanthomonas oryzae pv.oryzae to enhance immunity against the pathogen.In particular,OsWRKY65directly bound to the promoter region of OsSWEET13 and repressed its expression.Taken together,our findings demonstrate that the OsWRKY65 enhances resistance to fungal and bacterial pathogens in rice.
基金Supported by the National Natural Science Foundation of China(30971912)the Science and Technology Planning Project of the Colleges under Guangzhou Jurisdiction(08C030)+1 种基金the Guangzhou Science and Technology Planning Project(2008J1-C251-2)the"Yangcheng Scholars"Academic Backbone Project of the Colleges under Guangzhou Jurisdiction(10A042G)~~
文摘WRKY family proteins are a class of plant specific transcription factors that involve in many stress response pathways. It has been shown that one Arabidopsis WRKY protein, AtWRKY29/22, is activated by MAP kinase signaling cascade and confers resistance to both bacterial and fungal pathogens. However, little is known about the biological roles of WRKY proteins in rice. In this study, we investigated the expression patterns of rice AtWRKY29/22 homolog, OsWRKY03, under different conditions, and also its possible role involved in plant defense. Our results showed that OsWRKY03 was up-regulated by several defense signaling molecules or different treatments. Further analysis revealed that the expres- sion of OsWRKY03 was light dependent. Transcriptional activation activity of OsWRKY03 was also demonstrated by yeast functional assay. Transient expression of OsWRKY03-GFP fusion protein in onion epidermis cells showed that OsWRKY03 was a nuclear localized protein. OsNPR1 as well as several other pathogenesis-related genes, such as OsPR1b, phenylalanine ammonia-lyase (ZB8) and peroxidase (POX22.3), were induced in OsWRKY03-overexpressing transgenic plants. These results indicated that OsWRKY03 is located upstream of OsNPR1 as a transcriptional activator in salicylic acid (SA)-dependent or jasmonic acid (JA)-dependent defense signaling cascades.
基金funded by the National Key Research and Development Program of China(Grant No.2016YFD0100601-15)Zhejiang Fundamental Public Welfare Research Program(Grant No.LGN19C140008)+2 种基金Zhejiang Provincial Key Research and Development Plan(Grant No.2019C02006)Major Scientific and Technological Innovation 2025 Project of Ningbo(Grant No.2019B10004)Major Agricultural Science and Technology Project in Ningbo(Grant No.2016C11017).
文摘OsPRIOa is one of the well known pathogenesis-related genes in rice,and is induced by multiple plant hormones and pathogens.However,the underlying transcriptional regulation mechanisms in response to differe nt signals and their crosstalks are still largely unknown.In order to find new players participated in the activation of OsPRIOa,we systematically analyzed the basal expression patterns as well as the expression responses of a 2.5 kb OsPRIOa promoter in rice transgenic plants after phytohormone and pathogen stimulations.In agreement with the native gene expression,the OsPRIOa promoter can drive glucuronidase(GUS)gene expressing in spots of leaf cells,leaf trichomes,lemmas and paleae,germinating embryos,calli and root tips.The leaf expression of OsPR10a::GUS was dramatically in creased upon jasm onic acid(JA)and cytoki nin(CK)treatme nts,or challe nges of the pathogen Magnaporthe grisea and Xanthomonas oryzae pv.oryzae.Thus,the OsPRIOa promoter reported here can faithfully reflect its native gene expression.The effects of several JA and CK responsive OsWRKY genes on the regulation of OsPRIOa promoter were then inspected by luciferase transient expression assay,and the JA inducible OsWRKYlO transcription factor was found as a new positive regulator of OsPRIOa.However,the key transcription factors of JA and CK signaling pathways,OsMYC2 and B-type response regulators,were not responsible for the activation of OsPRIOa promote Our findings provided new in sights into the regulation of OsPRIOa expression during plan t-hormone/pathoge n interactions,and the OsPRIOa reporter system can be useful to unravel novel regulators from both pathogen and host.
基金Niche Area of Excellence-Indian Council for Agriculture Research[Grant No.10(15)/2012]Department of Science and Technology-Fund for Improvement of Science and Technology Infrastructure Government of India for providing financial support
文摘Plant WRKY transcription factors （TFs） constitute one of the largest families of proteinsinvolved in biotic and abiotic stress responses. These TFs have a conserved 60 amino acid WRKYdomain at the N-terminal and a zinc finger motif at the C-terminal. To examine the relevance ofOsWRKY72 in imparting salinity stress tolerance, two indica rice genotypes, Rasi （tolerant genotype）and Tellahamsa （susceptible genotype）, were used. In Rasi seedlings at 12 h under 100 mmol/L NaClstress, OsWRKY72 expression was up-regulated, whereas in Tellahamsa, it was highly up-regulated atlethal stress. Full-length OsWRKY72 cDNA was cloned from these two rice genotypes for furtheranalysis. We identified a variant, termed as OsWRKY72b that carries an additional sequence of 111 bpwithin the WRKY domain. Expression of OsWRKY72b was higher under salinity stress in Rasi than inTellahamsa. Disorder prediction of OsWRKY72b showed that the additional sequence in the WRKYdomain is ordered thereby maintaining the tertiary structure that might interact with the major groove ofDNA. Prediction of phosphorylation sites in OsWRKY72b indicated that a few serine residues could bethe potential phosphorylation sites. In this study, we firstly reported a OsWRKY72 variant that couldhave a role in abiotic stress responses.
