The NAC(NAM,ATAF1/2,and CUC2)is a defense-associated transcription factor(TF)family that positively regulates defense responses to pathogen infection.TaNAC069 positively regulates resistance in wheat to Puccinia triti...The NAC(NAM,ATAF1/2,and CUC2)is a defense-associated transcription factor(TF)family that positively regulates defense responses to pathogen infection.TaNAC069 positively regulates resistance in wheat to Puccinia triticina(Pt).However,the molecular mechanism of its interaction with a Pt effector is not clear.We found that Pt effector Pt-1234 interacts with TaNAC069 to subvert host immunity during Pt infection.Quantitative real-time PCR analysis showed that expression of Pt-1234 was significantly upregulated during the early stage of Pt infection.Protein-mediated cell death assays in wheat showed that the Pt-1234 protein was unable to induce cell death in wheat near-isogenic lines carrying different leaf rust resistance genes,whereas it suppressed BAX-induced cell death in leaves of Nicotiana benthamiana.Silencing of Pt-1234 by host-induced gene silencing(HIGS)significantly reduced the virulence of Pt in the susceptible wheat variety Thatcher.The C subdomain of TaNAC069 was responsible for its interaction with Pt-1234,and the E subdomain was required for TaNAC069-mediated defense responses to Pt in planta.These findings indicate that Pt utilizes Pt-1234 to interact with wheat transcription factor TaNAC069 through its C subdomain,thereby modulating wheat immunity.展开更多
An accurate assessment of host and pathogen gene expression during infection is critical for understanding the molecular aspects of host-pathogen interactions.Often,pathogen-derived transcripts are difficult to ascert...An accurate assessment of host and pathogen gene expression during infection is critical for understanding the molecular aspects of host-pathogen interactions.Often,pathogen-derived transcripts are difficult to ascertain at early infection stages owing to the unfavourable transcript representation compared to the host genes.In this study,we compare two sequencing techniques,RNAseq and enrichment sequencing(RenSeq and PenSeq)of cDNA,to investigate gene expression patterns in the doubled monoploid potato(DM)infected with the late blight pathogen Phytophthora infestans.Our results reveal distinct advantages of cDNA RenSeq and PenSeq over traditional RNAseq in terms of target gene representation and transcriptional quantification at early infection stages.Throughout the infection time course,cDNA enrichment sequencing enables transcriptomic analyses for more targeted host and pathogen genes.For highly expressed genes that were sampled in parallel by both cDNA enrichment and RNAseq,a high level of concordance in expression profiles is observed,indicative of at least semi-quantitative gene expression representation following enrichment.展开更多
Rice blast disease caused by Magnaporthe oryzae poses a serious threat to rice security worldwide.This filamentous pathogen modulates rice defense responses by secreting effectors to facilitate infection.The phytohorm...Rice blast disease caused by Magnaporthe oryzae poses a serious threat to rice security worldwide.This filamentous pathogen modulates rice defense responses by secreting effectors to facilitate infection.The phytohormone jasmonic acid(JA)plays crucial roles in the response to rice blast fungus.However,how M.oryzae disrupts JA-mediated resistance in rice is not well understood.In this study,we identify a new effector,a chloroplast-targeting protein(MoCHT1),from M.oryzae.Knocking out MoCHT1 decreases virulence,whereas heterologous expression of MoCHT1 in rice compromises disease resistance.MoCHT1 interacts with a rice LESION AND LAMINA BENDING(OsLLB)protein,a negative regulator of JA biosynthesis in the chloroplast.Loss-of-function of Os LLB leads to increased JA accumulation,thereby improving resistance to rice blast.The interaction between MoCHT1 and OsLLB results in the inhibition of OsLLB degradation,consequently reducing JA accumulation,thereby impairing JA content and decreasing plant disease resistance.Overall,this study reveals the molecular mechanism by which M.oryzae utilizes MoCHT1 to subvert rice JA signaling,broadening our understanding of how pathogens circumvent host immune responses by manipulating plant defense hormone biosynthesis.展开更多
The sugar beet cyst nematode(Heterodera schachtii) is one of the most destructive pathogens in sugar beet production, which causes serious economic losses every year. Few molecular details of effectors of H. schachtii...The sugar beet cyst nematode(Heterodera schachtii) is one of the most destructive pathogens in sugar beet production, which causes serious economic losses every year. Few molecular details of effectors of H. schachtii parasitism are known. We analyzed the genome and transcriptome data of H. schachtii and identified multiple potential predicted proteins. After filtering out predicted proteins with high homology to other plant-parasitic nematodes, we performed functional validation of the remaining effector proteins. 37 putative effectors of H. schachtii were screened based on the Nicotiana benthamiana system for identifying the effectors that inhibit plant immune response, eventually determines 13 candidate effectors could inhibit cell death caused by Bax. Among the 13 effectors, nine have the ability to inhibit GPA2/RBP1-induced cell death. All 13 effectortriggered immunity(ETI) suppressor genes were analyzed by qRT-PCR and confirmed to result in a significant downregulation of one or more defense genes during infection compared to empty vector. For in situ hybridization,13 effectors were specifically expressed and located in esophageal gland cells. These data and functional analysis set the stage for further studies on the interaction of H. schachtii with host and H. schachtii parasitic control.展开更多
The microstructure of high Nb-TiAl alloys was optimized by the addition of a small amount of Ta elements to further improve their properties.A series of Ti46Al1.5Cr8Nb-xTa(x=0.2,0.4,0.6,0.8,1.0,at.%)alloys were prepar...The microstructure of high Nb-TiAl alloys was optimized by the addition of a small amount of Ta elements to further improve their properties.A series of Ti46Al1.5Cr8Nb-xTa(x=0.2,0.4,0.6,0.8,1.0,at.%)alloys were prepared by vacuum arc melting.The microstructure,mechanical properties,and related influencing mechanisms were systematically investigated.The results indicate that the solidification microstructure of the Ti46Al1.5Cr8Nb-xTa alloys comprises theγ-TiAl phase,α_(2)-Ti_(3)Al phase,and B2 phase.As the Ta content increases from 0.2 at.%to 1.0 at.%,the content ofα_(2)phase and B2 phase increases,while theγphase content decreases.Among them,the B2 phase shows the most pronounced change,being significantly refined,with its content increasing from 12.49%to 21.91%.In addition,the average size of the lamellar colony decreases from 160.65 to 94.44μm.The addition of the Ta element shifts the solidification path toward lower aluminum concentrations,leading to changes in phase content.The tantalum-induced increase in the B2 phase and enhanced supercooling at the solidification front provide the basis for lamellar colony refinement.Compressive testing at room temperature reveals that the Ti46 Al1.5 Cr8 Nb0.4 Ta alloy exhibits optimal compressive properties,achieving a compressive strength of 2,434 MPa and a compressive strain of 33.1%.The improvement of its properties is attributed to a combination of lamellar colony refinement,solid solution strengthening resulting from the incorporation of Ta element,and a reduction in the c/a of theγphase.展开更多
基金funded by State Key Laboratory of North China Crop Improvement and Regulation(NCCIR2023ZZ-10)the National Natural Science Foundation of China(32172384 and 31501623)+1 种基金the Natural Science Foundation of Hebei(C2020204028)the Science and Technology Research Project of Higher Education of Hebei(ZC2023178).
文摘The NAC(NAM,ATAF1/2,and CUC2)is a defense-associated transcription factor(TF)family that positively regulates defense responses to pathogen infection.TaNAC069 positively regulates resistance in wheat to Puccinia triticina(Pt).However,the molecular mechanism of its interaction with a Pt effector is not clear.We found that Pt effector Pt-1234 interacts with TaNAC069 to subvert host immunity during Pt infection.Quantitative real-time PCR analysis showed that expression of Pt-1234 was significantly upregulated during the early stage of Pt infection.Protein-mediated cell death assays in wheat showed that the Pt-1234 protein was unable to induce cell death in wheat near-isogenic lines carrying different leaf rust resistance genes,whereas it suppressed BAX-induced cell death in leaves of Nicotiana benthamiana.Silencing of Pt-1234 by host-induced gene silencing(HIGS)significantly reduced the virulence of Pt in the susceptible wheat variety Thatcher.The C subdomain of TaNAC069 was responsible for its interaction with Pt-1234,and the E subdomain was required for TaNAC069-mediated defense responses to Pt in planta.These findings indicate that Pt utilizes Pt-1234 to interact with wheat transcription factor TaNAC069 through its C subdomain,thereby modulating wheat immunity.
基金supported by the Rural & Environment Science & Analytical Services (RESAS) Division of the Scottish Government through project JHI-B1-1the Biotechnology and Biological Sciences Research Council (BBSRC) through awards BB/ S015663/1+2 种基金BB/X009068/1Research Leaders 2025 fellowship funded by European Union’s Horizon 2020 research and innovation programme under Marie Sklodowska-Curie grant agreement no. 754380the Research/Scientific Computing teams at The James Hutton Institute and NIAB for providing computational resources and technical support for the “UK’s Crop Diversity Bioinformatics HPC” (BBSRC grant BB/ S019669/1)。
文摘An accurate assessment of host and pathogen gene expression during infection is critical for understanding the molecular aspects of host-pathogen interactions.Often,pathogen-derived transcripts are difficult to ascertain at early infection stages owing to the unfavourable transcript representation compared to the host genes.In this study,we compare two sequencing techniques,RNAseq and enrichment sequencing(RenSeq and PenSeq)of cDNA,to investigate gene expression patterns in the doubled monoploid potato(DM)infected with the late blight pathogen Phytophthora infestans.Our results reveal distinct advantages of cDNA RenSeq and PenSeq over traditional RNAseq in terms of target gene representation and transcriptional quantification at early infection stages.Throughout the infection time course,cDNA enrichment sequencing enables transcriptomic analyses for more targeted host and pathogen genes.For highly expressed genes that were sampled in parallel by both cDNA enrichment and RNAseq,a high level of concordance in expression profiles is observed,indicative of at least semi-quantitative gene expression representation following enrichment.
基金funded by the Biological Breeding-National Science and Technology Major Projects(2023ZD04070)the National Natural Science Foundation of China(31970284,31900385)+1 种基金the Fujian Provincial Science and Technology Key Project(2022NZ030014)the Natural Science Foundation of Fujian Province,China(2023J01483,2022J01616)。
文摘Rice blast disease caused by Magnaporthe oryzae poses a serious threat to rice security worldwide.This filamentous pathogen modulates rice defense responses by secreting effectors to facilitate infection.The phytohormone jasmonic acid(JA)plays crucial roles in the response to rice blast fungus.However,how M.oryzae disrupts JA-mediated resistance in rice is not well understood.In this study,we identify a new effector,a chloroplast-targeting protein(MoCHT1),from M.oryzae.Knocking out MoCHT1 decreases virulence,whereas heterologous expression of MoCHT1 in rice compromises disease resistance.MoCHT1 interacts with a rice LESION AND LAMINA BENDING(OsLLB)protein,a negative regulator of JA biosynthesis in the chloroplast.Loss-of-function of Os LLB leads to increased JA accumulation,thereby improving resistance to rice blast.The interaction between MoCHT1 and OsLLB results in the inhibition of OsLLB degradation,consequently reducing JA accumulation,thereby impairing JA content and decreasing plant disease resistance.Overall,this study reveals the molecular mechanism by which M.oryzae utilizes MoCHT1 to subvert rice JA signaling,broadening our understanding of how pathogens circumvent host immune responses by manipulating plant defense hormone biosynthesis.
基金supported by the Open Fund of the Key Laboratory of Integrated Pest Management on Crop in Northwestern Oasis,Ministry of Agriculture and Rural Affairsof China(KFJJ202101)the National KeyR&D Program of China(2021YFD1400100)+1 种基金the National Natural Science Foundation of China(31972247)the Tianchi Talent Introduction Program in Xinjiang Uygur Autonomous Region,China and the Science and Technology Innovation Project of the Chinese Academy of Agricultural Sciences.
文摘The sugar beet cyst nematode(Heterodera schachtii) is one of the most destructive pathogens in sugar beet production, which causes serious economic losses every year. Few molecular details of effectors of H. schachtii parasitism are known. We analyzed the genome and transcriptome data of H. schachtii and identified multiple potential predicted proteins. After filtering out predicted proteins with high homology to other plant-parasitic nematodes, we performed functional validation of the remaining effector proteins. 37 putative effectors of H. schachtii were screened based on the Nicotiana benthamiana system for identifying the effectors that inhibit plant immune response, eventually determines 13 candidate effectors could inhibit cell death caused by Bax. Among the 13 effectors, nine have the ability to inhibit GPA2/RBP1-induced cell death. All 13 effectortriggered immunity(ETI) suppressor genes were analyzed by qRT-PCR and confirmed to result in a significant downregulation of one or more defense genes during infection compared to empty vector. For in situ hybridization,13 effectors were specifically expressed and located in esophageal gland cells. These data and functional analysis set the stage for further studies on the interaction of H. schachtii with host and H. schachtii parasitic control.
基金the financial support by the Major Science and Technology Achievement Transformation Project in Heilongjiang Province(No.ZC2023SH0075)the National Natural Science Foundation of China(Nos.52425401,U2441255,52474377,and 52371015)+1 种基金the Young Elite Scientists Sponsorship·Program by CAST(No.2021QNRC001)the Henan Provincial Key Research and Development&Promotion Special Program(No.251111231400)。
文摘The microstructure of high Nb-TiAl alloys was optimized by the addition of a small amount of Ta elements to further improve their properties.A series of Ti46Al1.5Cr8Nb-xTa(x=0.2,0.4,0.6,0.8,1.0,at.%)alloys were prepared by vacuum arc melting.The microstructure,mechanical properties,and related influencing mechanisms were systematically investigated.The results indicate that the solidification microstructure of the Ti46Al1.5Cr8Nb-xTa alloys comprises theγ-TiAl phase,α_(2)-Ti_(3)Al phase,and B2 phase.As the Ta content increases from 0.2 at.%to 1.0 at.%,the content ofα_(2)phase and B2 phase increases,while theγphase content decreases.Among them,the B2 phase shows the most pronounced change,being significantly refined,with its content increasing from 12.49%to 21.91%.In addition,the average size of the lamellar colony decreases from 160.65 to 94.44μm.The addition of the Ta element shifts the solidification path toward lower aluminum concentrations,leading to changes in phase content.The tantalum-induced increase in the B2 phase and enhanced supercooling at the solidification front provide the basis for lamellar colony refinement.Compressive testing at room temperature reveals that the Ti46 Al1.5 Cr8 Nb0.4 Ta alloy exhibits optimal compressive properties,achieving a compressive strength of 2,434 MPa and a compressive strain of 33.1%.The improvement of its properties is attributed to a combination of lamellar colony refinement,solid solution strengthening resulting from the incorporation of Ta element,and a reduction in the c/a of theγphase.
