Exosomes are cell-derived vesicles that are secreted by many eukaryotic cells. It has recently attracted attention as vehicles of intercellular communication. Virus-infected cells release exosomes, which contain viral...Exosomes are cell-derived vesicles that are secreted by many eukaryotic cells. It has recently attracted attention as vehicles of intercellular communication. Virus-infected cells release exosomes, which contain viral proteins, RNA, and pathogenic molecules. However, the role of exosomes in virus infection process remains unclear and needs to be further investigated.In this study, we aimed to evaluate the effects of exosomes on rabies virus infection. OptiPrep^(TM) density gradient centrifugation was used to isolate exosomes from rabies virus-infected cell culture supernatants. A rabies virus G protein enzyme-linked immunosorbent assay and acetylcholinesterase activity assays were performed to verify the centrifugation fractions. Exosomes were then characterized using transmission electron microscopy and Western blotting. Our results showed that rabies virus infection increased the release of exosomes. Treatment with GW4869 and si-Rab27 a, two exosomal secretion inhibitors, inhibited exosome release. Furthermore, the inhibitors reduced the levels of extracellular and intracellular viral RNA. These data indicated that exosomes may participate in the viral infection process. Moreover, our results establish a basis for future research into the roles of exosomes in rabies virus infection and as potential targets for developing new antiviral strategies.展开更多
The Enterovirus 71(EV71)VP4 is co-translationally linked to myristic acid at its amino-terminal glycine residue.However,the role of this myristoylation in the EV71 life cycle remains largely unknown.To investigate thi...The Enterovirus 71(EV71)VP4 is co-translationally linked to myristic acid at its amino-terminal glycine residue.However,the role of this myristoylation in the EV71 life cycle remains largely unknown.To investigate this issue,we developed a myristoylation-deficient virus and reporter(luciferase)pseudovirus with a Gly-to-Ala mutation(G2A)on EV71 VP4.When transfecting the EV71-G2 A genome encoding plasmid in cells,the loss of myristoylation on VP4 did not affect the expression of viral proteins and the virus morphology,however,it did significantly influence viral infectivity.Further,in myristoylation-deficient reporter pseudovirus-infected cells,the luciferase activity and viral genome RNA decreased significantly as compared to that of wild type virus;however,cytopathic effect and viral capsid proteins were not detected in myristoylation-deficient virus-infected cells.Also,although myristoylation-deficient viral RNA and proteins were detected in the second blind passage of infection,they were much fewer in number compared to that of the wild type virus.The replication of genomic RNA and negative-strand viral RNA were both blocked in myristoylation-deficient viruses,suggesting that myristoylation affects viral genome RNA release from capsid to cytoplasm.Besides,loss of myristoylation on VP4 altered the distribution of VP4-green fluorescent protein protein,which disappeared from the membrane structure fraction.Finally,a liposome leakage assay showed that EV71 myristoylation mediates the permeability of the model membrane.Hence,the amino-terminal myristoylation of VP4 is pivotal to EV71 infection and capsidmembrane structure interaction.This study provides novel molecular mechanisms regarding EV71 infection and potential molecular targets for antiviral drug design.展开更多
Leaf color mutants are ideal materials for studying many plant physiological and metabolic processes such as photosynthesis,photomorphogenesis,hormone physiology and disease resistance.In this study,the genetically st...Leaf color mutants are ideal materials for studying many plant physiological and metabolic processes such as photosynthesis,photomorphogenesis,hormone physiology and disease resistance.In this study,the genetically stable yellow-green leaf mutant ygl16 was identified from mutated“Xinong 1B”.Compared with the wild type,the pigment concentration and photosynthetic capacity of the ygl16 decreased significantly.The ultrastructural observation showed that the distribution of thylakoid lamellae was irregular in ygl16 chloroplasts,and the grana and matrix lamellae were blurred and loose in varied degrees,and the chloroplast structure was disordered,while the osmiophilic corpuscles increased.The results of the genetic analysis and mapping showed that the phenotype of ygl16 was controlled by a pair of recessive nuclear gene.The gene located in the 56Kb interval between RM25654 and R3 on the long arm of chromosome 10.The sequencing results showed that the 121st base of the first intron of the candidate gene OsPORB/FGL changed from A to T in the interval.qRT-PCR results showed that the expression of chlorophyll synthase-related genes in the mutant decreased.展开更多
As an intangible property right,intellectual property is a very important economic resource,which is of great significance for merchants to enter the international market.With the development of The Times,more and mor...As an intangible property right,intellectual property is a very important economic resource,which is of great significance for merchants to enter the international market.With the development of The Times,more and more merchants begin to look globally and enter the overseas market.In order to gain a foothold and develop in the international market where intellectual property rights are more strictly protected,intellectual property rights have important significance that cannot be ignored by all businesses.Writing significance:Taking NetEase Koala as an example to further understand the IPR protection of cross-border e-commerce.展开更多
Acetylation of N^(4)-cytidine(ac^(4)C)has recently been discovered as a novel modification of mRNA.RNA ac^(4)C modification has been shown to be a key regulator of RNA stability,RNA translation,and the thermal stress ...Acetylation of N^(4)-cytidine(ac^(4)C)has recently been discovered as a novel modification of mRNA.RNA ac^(4)C modification has been shown to be a key regulator of RNA stability,RNA translation,and the thermal stress response.However,its existence in eukaryotic mRNAs is still controversial.In plants,the existence,distribution pattern,and potential function of RNA ac^(4)C modification are largely unknown.Here we report the presence of ac^(4)C in the mRNAs of both Arabidopsis thaliana and rice(Oryza sativa).By comparing two ac^(4)C sequencing methods,we found that RNA immunoprecipitation and sequencing(acRIP-seq),but not ac^(4)C sequencing,was suitable for plant RNA ac^(4)C sequencing.We present transcriptome-wide atlases of RNA ac^(4)C modification in A.thaliana and rice mRNAs obtained by acRIP-seq.Analysis of the distribution of RNA ac^(4)C modifications showed that ac^(4)C is enriched near translation start sites in rice mRNAs and near translation start sites and translation end sites in Arabidopsis mRNAs.The RNA ac^(4)C modification level is positively correlated with RNA half-life and the number of splicing variants.Similar to that in mammals,the translation efficiency of ac^(4)C target genes is significantly higher than that of other genes.Our in vitro translation results confirmed that RNA ac^(4)C modification enhances translation efficiency.We also found that RNA ac^(4)C modification is negatively correlated with RNA structure.These results suggest that ac^(4)C is a conserved mRNA modification in plants that contributes to RNA stability,splicing,translation,and secondary structure formation.展开更多
基金supported by the National Natural Science Foundation of China (Grant No. 31770184)Construction Project of Provincial-School of Jilin Province (No. 440050316A28)
文摘Exosomes are cell-derived vesicles that are secreted by many eukaryotic cells. It has recently attracted attention as vehicles of intercellular communication. Virus-infected cells release exosomes, which contain viral proteins, RNA, and pathogenic molecules. However, the role of exosomes in virus infection process remains unclear and needs to be further investigated.In this study, we aimed to evaluate the effects of exosomes on rabies virus infection. OptiPrep^(TM) density gradient centrifugation was used to isolate exosomes from rabies virus-infected cell culture supernatants. A rabies virus G protein enzyme-linked immunosorbent assay and acetylcholinesterase activity assays were performed to verify the centrifugation fractions. Exosomes were then characterized using transmission electron microscopy and Western blotting. Our results showed that rabies virus infection increased the release of exosomes. Treatment with GW4869 and si-Rab27 a, two exosomal secretion inhibitors, inhibited exosome release. Furthermore, the inhibitors reduced the levels of extracellular and intracellular viral RNA. These data indicated that exosomes may participate in the viral infection process. Moreover, our results establish a basis for future research into the roles of exosomes in rabies virus infection and as potential targets for developing new antiviral strategies.
基金supported by the National Natural Science Foundation of China(Grant No.31770184)
文摘The Enterovirus 71(EV71)VP4 is co-translationally linked to myristic acid at its amino-terminal glycine residue.However,the role of this myristoylation in the EV71 life cycle remains largely unknown.To investigate this issue,we developed a myristoylation-deficient virus and reporter(luciferase)pseudovirus with a Gly-to-Ala mutation(G2A)on EV71 VP4.When transfecting the EV71-G2 A genome encoding plasmid in cells,the loss of myristoylation on VP4 did not affect the expression of viral proteins and the virus morphology,however,it did significantly influence viral infectivity.Further,in myristoylation-deficient reporter pseudovirus-infected cells,the luciferase activity and viral genome RNA decreased significantly as compared to that of wild type virus;however,cytopathic effect and viral capsid proteins were not detected in myristoylation-deficient virus-infected cells.Also,although myristoylation-deficient viral RNA and proteins were detected in the second blind passage of infection,they were much fewer in number compared to that of the wild type virus.The replication of genomic RNA and negative-strand viral RNA were both blocked in myristoylation-deficient viruses,suggesting that myristoylation affects viral genome RNA release from capsid to cytoplasm.Besides,loss of myristoylation on VP4 altered the distribution of VP4-green fluorescent protein protein,which disappeared from the membrane structure fraction.Finally,a liposome leakage assay showed that EV71 myristoylation mediates the permeability of the model membrane.Hence,the amino-terminal myristoylation of VP4 is pivotal to EV71 infection and capsidmembrane structure interaction.This study provides novel molecular mechanisms regarding EV71 infection and potential molecular targets for antiviral drug design.
基金supported by grants from the Project of Creating High Quality,Disease Resistance and High Combining Ability CMS Lines(Grant No.cstc2018jscx-msybX0250)Chongqing Technology Innovation and Application Demonstration Project and the Project of High Photosynthetic Efficiency Rice Breeding Technology System(Grant No.2017YFD0100201)the National Key Research and Development Program“Seven Crops Breeding”.
文摘Leaf color mutants are ideal materials for studying many plant physiological and metabolic processes such as photosynthesis,photomorphogenesis,hormone physiology and disease resistance.In this study,the genetically stable yellow-green leaf mutant ygl16 was identified from mutated“Xinong 1B”.Compared with the wild type,the pigment concentration and photosynthetic capacity of the ygl16 decreased significantly.The ultrastructural observation showed that the distribution of thylakoid lamellae was irregular in ygl16 chloroplasts,and the grana and matrix lamellae were blurred and loose in varied degrees,and the chloroplast structure was disordered,while the osmiophilic corpuscles increased.The results of the genetic analysis and mapping showed that the phenotype of ygl16 was controlled by a pair of recessive nuclear gene.The gene located in the 56Kb interval between RM25654 and R3 on the long arm of chromosome 10.The sequencing results showed that the 121st base of the first intron of the candidate gene OsPORB/FGL changed from A to T in the interval.qRT-PCR results showed that the expression of chlorophyll synthase-related genes in the mutant decreased.
文摘As an intangible property right,intellectual property is a very important economic resource,which is of great significance for merchants to enter the international market.With the development of The Times,more and more merchants begin to look globally and enter the overseas market.In order to gain a foothold and develop in the international market where intellectual property rights are more strictly protected,intellectual property rights have important significance that cannot be ignored by all businesses.Writing significance:Taking NetEase Koala as an example to further understand the IPR protection of cross-border e-commerce.
基金support from the National Natural Science Foundation of China(32070613,32270623)the Science and Technology Innovation Program of Hunan Province(2021RC3045)+1 种基金support from the National Natural Science Foundation of China(U20A2029)support from the Postgraduate Scientific Research Innovation Project of Hunan Province(CX20200468).
文摘Acetylation of N^(4)-cytidine(ac^(4)C)has recently been discovered as a novel modification of mRNA.RNA ac^(4)C modification has been shown to be a key regulator of RNA stability,RNA translation,and the thermal stress response.However,its existence in eukaryotic mRNAs is still controversial.In plants,the existence,distribution pattern,and potential function of RNA ac^(4)C modification are largely unknown.Here we report the presence of ac^(4)C in the mRNAs of both Arabidopsis thaliana and rice(Oryza sativa).By comparing two ac^(4)C sequencing methods,we found that RNA immunoprecipitation and sequencing(acRIP-seq),but not ac^(4)C sequencing,was suitable for plant RNA ac^(4)C sequencing.We present transcriptome-wide atlases of RNA ac^(4)C modification in A.thaliana and rice mRNAs obtained by acRIP-seq.Analysis of the distribution of RNA ac^(4)C modifications showed that ac^(4)C is enriched near translation start sites in rice mRNAs and near translation start sites and translation end sites in Arabidopsis mRNAs.The RNA ac^(4)C modification level is positively correlated with RNA half-life and the number of splicing variants.Similar to that in mammals,the translation efficiency of ac^(4)C target genes is significantly higher than that of other genes.Our in vitro translation results confirmed that RNA ac^(4)C modification enhances translation efficiency.We also found that RNA ac^(4)C modification is negatively correlated with RNA structure.These results suggest that ac^(4)C is a conserved mRNA modification in plants that contributes to RNA stability,splicing,translation,and secondary structure formation.
