Turnip mosaic virus(TuMV)is a devastating potyvirus pathogen that infects a wide variety of both cultivated and wild Brassicaceae plants.We urgently need more information and understanding of TuMV pathogenesis and the...Turnip mosaic virus(TuMV)is a devastating potyvirus pathogen that infects a wide variety of both cultivated and wild Brassicaceae plants.We urgently need more information and understanding of TuMV pathogenesis and the host responses involved in disease development in cruciferous crops.TuMV displays great versatility in viral pathogenesis,especially in its replication and intercellular movement.Moreover,in the coevolutionary arms races between TuMV and its hosts,the virus has evolved to co-opt host factors to facilitate its infection and counter host defense responses.This review mainly focuses on recent advances in understanding the viral factors that contribute to the TuMV infection cycle and the host resistance mechanism in Brassica.Finally,we propose some future research directions on TuMV pathogenesis and control strategies to design durable TuMV-resistant Brassica crops.展开更多
Complementary DNAs to turnip mosaic virus (a radish Raphanus stativus isolate) genomicRNA were synthesized using oligo (dT) as primer and cloned into the vector λ-ZAP Ⅱ. Afterhybridization with a single-stranded cDN...Complementary DNAs to turnip mosaic virus (a radish Raphanus stativus isolate) genomicRNA were synthesized using oligo (dT) as primer and cloned into the vector λ-ZAP Ⅱ. Afterhybridization with a single-stranded cDNA probe and the sequencing of inserted DNA,positive clones with poly--A tails were obtained. One clone containing 1429-base pair insertwas sequenced. The coat protein gene was identified based on the molecular weight of theTuMV coat protein and the consensus sequences of the polyprotein processing sites ofpotyviruses. The 5’ end of the coat protein gene was modified by PCR to introduce aninitiation codon, ATG, and two restriction enzyme sites. The gene was then manipulatedinto a binary vector pBIN437 which was derived from pBI121, and the plant expressionvector is being used to transform Brassica napus.展开更多
DNA methylation is an important epigenetic marker for the suppression of transposable elements(TEs)and the regu-lation of plant immunity.However,little is known how RNA viruses counter defense such antiviral machinery...DNA methylation is an important epigenetic marker for the suppression of transposable elements(TEs)and the regu-lation of plant immunity.However,little is known how RNA viruses counter defense such antiviral machinery.In this study,the change of DNA methylation in turnip mosaic virus(TuMV)-infected cells was analyzed by whole genome bisulfite sequencing.Results showed that the total number of methylated sites of CHH and CHG increased in TuMV-infected cells,the majority of differentially methylated regions(DMRs)in the CHH and CHG contexts were associated with hypermethylation.Gene expression analysis showed that the expression of two methylases(DRM2 and CMT3)and three demethylases(ROS3,DML2,DML3)was significantly increased and decreased in TuMV-infected cells,respec-tively.Pathogenicity tests showed that the enhanced resistance to TuMV of the loss-of-function mutant of DRM2 is associated with unregulated expression of several defense-related genes.Finally,we found TuMV-encoded NIb,the viral RNA-dependent RNA polymerase,was able to induce the expression of DRM2.In conclusion,this study discov-ered that TuMV can modulate host DNA methylation by regulating the expression of DRM2 to promote virus infection.展开更多
“8407”is a disease resistant germplasm of Chinese cabbage which is highly resis-tant to turnip mosaic virus (TuMV),selected by the Vegetable Institute,Hebei Academy of Agri-cultural and Forestry Sciences.In 1985 and...“8407”is a disease resistant germplasm of Chinese cabbage which is highly resis-tant to turnip mosaic virus (TuMV),selected by the Vegetable Institute,Hebei Academy of Agri-cultural and Forestry Sciences.In 1985 and 1989,it was approved and accepted as one of the na-tional disease resistant germplasm of Chinese cabbage by the National Expert Group.The identifi-cation in 1989 showed that“8407”was highly resistant or immune to 19 TuMV strains from 10provinces/cities across the country.Therefore,it was regarded as the best germplasm both verti-cally and horizontally resistant to TuMV of Chinese cabbage.This germplasm was selected fromChang Paodan (Inner Mongolia)of Qingmaye system after 6 generations of successive self cross.Using the disease resistant germplasm of“8407”,we developed new multi-resistant varieties of“8361”and“8612”in 1983 and 1986 respectively,which was highly resistant to TuMV and downymildew and soft rot.These varieties have been extended to an areas of over 20000 ha.展开更多
Positive-sense single-stranded RNA(+ssRNA)viruses,the most abundant viruses of eukaryotes in nature,require the synthesis of negative-sense RNA(-RNA)using their genomic(positive-sense)RNA(+RNA)as a template for replic...Positive-sense single-stranded RNA(+ssRNA)viruses,the most abundant viruses of eukaryotes in nature,require the synthesis of negative-sense RNA(-RNA)using their genomic(positive-sense)RNA(+RNA)as a template for replication.Based on current evidence,viral proteins are translated via viral+RNAs,whereas-RNA is considered to be a viral replication intermediate without coding capacity.Here,we report that plant and animal+ssRNA viruses contain small open reading frames(ORFs)in their-RNA(reverse ORFs[rORFs]).Using turnip mosaic virus(TuMV)as a model for plant+ssRNA viruses,we demonstrate that small proteins encoded by rORFs display specific subcellularlocalizations,and confirm the presence of rORF2 in infected cells through mass spectrometry analysis.The protein encoded by TuMV rORF2 forms punctuate granules that are localized in the perinuclear region and co-localized with viral replication complexes.The rORF2 protein can directly interact with the viral RNA-dependent RNA polymerase,and mutation of rORF2 completely abolishes virus infection,whereas ectopic expression of rORF2 rescues the mutant virus.Furthermore,we show that several rORFs in the-RNA of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)have the ability to suppress type l interferon production and facilitate the infection of ve-sicular stomatitis virus.In addition,we provide evidence that TuMV might utilize internal ribosome entry sites to translate these small rORFs.Taken together,these findings indicate that the-RNA of+ssRNA vi-ruses can also have the coding capacity and that small proteins encoded therein play critical roles in viral infection,revealing a viral proteome larger than previously thought.展开更多
基金supported by a grant from Chinese Agriculture Research System of MOF and MARA (Grant No.CARS-24-C-04)Zhejiang Provincial Natural Science Foundation (Grant No.LZ24C140001)+1 种基金National Natural Science Foundation of China (Grant Nos.32370144,32070165)the K.C.Wong Magna Fund in Ningbo University。
文摘Turnip mosaic virus(TuMV)is a devastating potyvirus pathogen that infects a wide variety of both cultivated and wild Brassicaceae plants.We urgently need more information and understanding of TuMV pathogenesis and the host responses involved in disease development in cruciferous crops.TuMV displays great versatility in viral pathogenesis,especially in its replication and intercellular movement.Moreover,in the coevolutionary arms races between TuMV and its hosts,the virus has evolved to co-opt host factors to facilitate its infection and counter host defense responses.This review mainly focuses on recent advances in understanding the viral factors that contribute to the TuMV infection cycle and the host resistance mechanism in Brassica.Finally,we propose some future research directions on TuMV pathogenesis and control strategies to design durable TuMV-resistant Brassica crops.
文摘Complementary DNAs to turnip mosaic virus (a radish Raphanus stativus isolate) genomicRNA were synthesized using oligo (dT) as primer and cloned into the vector λ-ZAP Ⅱ. Afterhybridization with a single-stranded cDNA probe and the sequencing of inserted DNA,positive clones with poly--A tails were obtained. One clone containing 1429-base pair insertwas sequenced. The coat protein gene was identified based on the molecular weight of theTuMV coat protein and the consensus sequences of the polyprotein processing sites ofpotyviruses. The 5’ end of the coat protein gene was modified by PCR to introduce aninitiation codon, ATG, and two restriction enzyme sites. The gene was then manipulatedinto a binary vector pBIN437 which was derived from pBI121, and the plant expressionvector is being used to transform Brassica napus.
基金supported by the National Natural Science Foundation of China(32022071,31860491)the Natural Science Foundation of Heilongjiang Province(Grant No.LH2019C027)+1 种基金the Academic Backbone Projects of Northeast Agricultural University(18XG04)the project of China National Tobacco Corporation(110202002010-JY-13).
文摘DNA methylation is an important epigenetic marker for the suppression of transposable elements(TEs)and the regu-lation of plant immunity.However,little is known how RNA viruses counter defense such antiviral machinery.In this study,the change of DNA methylation in turnip mosaic virus(TuMV)-infected cells was analyzed by whole genome bisulfite sequencing.Results showed that the total number of methylated sites of CHH and CHG increased in TuMV-infected cells,the majority of differentially methylated regions(DMRs)in the CHH and CHG contexts were associated with hypermethylation.Gene expression analysis showed that the expression of two methylases(DRM2 and CMT3)and three demethylases(ROS3,DML2,DML3)was significantly increased and decreased in TuMV-infected cells,respec-tively.Pathogenicity tests showed that the enhanced resistance to TuMV of the loss-of-function mutant of DRM2 is associated with unregulated expression of several defense-related genes.Finally,we found TuMV-encoded NIb,the viral RNA-dependent RNA polymerase,was able to induce the expression of DRM2.In conclusion,this study discov-ered that TuMV can modulate host DNA methylation by regulating the expression of DRM2 to promote virus infection.
文摘“8407”is a disease resistant germplasm of Chinese cabbage which is highly resis-tant to turnip mosaic virus (TuMV),selected by the Vegetable Institute,Hebei Academy of Agri-cultural and Forestry Sciences.In 1985 and 1989,it was approved and accepted as one of the na-tional disease resistant germplasm of Chinese cabbage by the National Expert Group.The identifi-cation in 1989 showed that“8407”was highly resistant or immune to 19 TuMV strains from 10provinces/cities across the country.Therefore,it was regarded as the best germplasm both verti-cally and horizontally resistant to TuMV of Chinese cabbage.This germplasm was selected fromChang Paodan (Inner Mongolia)of Qingmaye system after 6 generations of successive self cross.Using the disease resistant germplasm of“8407”,we developed new multi-resistant varieties of“8361”and“8612”in 1983 and 1986 respectively,which was highly resistant to TuMV and downymildew and soft rot.These varieties have been extended to an areas of over 20000 ha.
基金funded by the National Key Research and Development Program of China(2021YFD1400400)to F.L.the National Natural Science Foundation of China(31930089 and 31972244)to X.Z.and F.L.+2 种基金a startup grant for High-level Talents of Fujian Medical University(XRCZX2019019)the Natural Science Foundation of Fujan Province,China(2020J01604)to Q.S.Work in the R.L.-D.lab is partially funded by the ERC-COG grant GemOmics(101044142)to R.L.-D.
文摘Positive-sense single-stranded RNA(+ssRNA)viruses,the most abundant viruses of eukaryotes in nature,require the synthesis of negative-sense RNA(-RNA)using their genomic(positive-sense)RNA(+RNA)as a template for replication.Based on current evidence,viral proteins are translated via viral+RNAs,whereas-RNA is considered to be a viral replication intermediate without coding capacity.Here,we report that plant and animal+ssRNA viruses contain small open reading frames(ORFs)in their-RNA(reverse ORFs[rORFs]).Using turnip mosaic virus(TuMV)as a model for plant+ssRNA viruses,we demonstrate that small proteins encoded by rORFs display specific subcellularlocalizations,and confirm the presence of rORF2 in infected cells through mass spectrometry analysis.The protein encoded by TuMV rORF2 forms punctuate granules that are localized in the perinuclear region and co-localized with viral replication complexes.The rORF2 protein can directly interact with the viral RNA-dependent RNA polymerase,and mutation of rORF2 completely abolishes virus infection,whereas ectopic expression of rORF2 rescues the mutant virus.Furthermore,we show that several rORFs in the-RNA of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)have the ability to suppress type l interferon production and facilitate the infection of ve-sicular stomatitis virus.In addition,we provide evidence that TuMV might utilize internal ribosome entry sites to translate these small rORFs.Taken together,these findings indicate that the-RNA of+ssRNA vi-ruses can also have the coding capacity and that small proteins encoded therein play critical roles in viral infection,revealing a viral proteome larger than previously thought.
