Pattern-triggered immunity(PTI)and effector-triggered immunity(ETI)are required for host defense against pathogens.Although PTI and ETI are intimately connected,the underlying molecular mechanisms remain elusive.In th...Pattern-triggered immunity(PTI)and effector-triggered immunity(ETI)are required for host defense against pathogens.Although PTI and ETI are intimately connected,the underlying molecular mechanisms remain elusive.In this study,we demonstrate that flg22 priming attenuates Pseudomonas syringae pv.tomato DC3000(Pst)AvrRpt2-induced hypersensitive cell death,resistance,and biomass reduction in Arabidopsis.Mitogen-activated protein kinases(MAPKs)are key signaling regulators of PTI and ETI.The absence of MPK3 and MPK6 significantly reduces pre-PTI-mediated ETI suppression(PES).We found that MPK3/MPK6 interact with and phosphorylate the downstream transcription factor WRKY18,which regulates the expression of AP2C1 and PP2C5,two genes encoding protein phosphatases.Furthermore,we observed that the PTI-suppressed ETI-triggered cell death,MAPK activation,and growth retardation are significantly attenuated in wrky18/40/60 and ap2c1 pp2c5 mutants.Taken together,our results suggest that the MPK3/MPK6-WRKYs-PP2Cs module underlies PES and is essential for the maintenance of plant fitness during ETI.展开更多
SARS-CoV-2 has caused over 100 million deaths and continues to spread rapidly around the world.Asymptomatic transmission of SARS-CoV-2 is the Achilles’heel of COVID-19 public health control measures.Phylogenomic data...SARS-CoV-2 has caused over 100 million deaths and continues to spread rapidly around the world.Asymptomatic transmission of SARS-CoV-2 is the Achilles’heel of COVID-19 public health control measures.Phylogenomic data on SARS-CoV-2 could provide more direct information about asymptomatic transmission.In this study,using a novel MINERVA sequencing technology,we traced asymptomatic transmission of COVID-19 patients in Beijing,China.One hundred and seventy-eight close contacts were quarantined,and 14 COVID-19 patients were laboratory confirmed by RT-PCR.We provide direct phylogenomic evidence of asymptomatic transmission by constructing the median joining network in the cluster.These data could help us to determine whether the current symptom-based screening should cover asymptomatic persons.展开更多
Introduction:In November 2021,the severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)Omicron variant was identified as the variant of concern and has since spread globally,replacing other cocirculating variant...Introduction:In November 2021,the severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)Omicron variant was identified as the variant of concern and has since spread globally,replacing other cocirculating variants.To better understand the dynamic changes in viral load over time and the natural history of the virus infection,we analyzed the expression of the open reading frames 1ab(ORF1ab)and nucleocapsid(N)genes in patients infected with Omicron.Methods:We included patients initially admitted to the hospital for SARS-CoV-2 infection between November 5 and December 25,2022.We collected daily oropharyngeal swabs for quantitative reverse transcriptase-polymerase chain reaction tests using commercial kits.We depicted the cycle threshold(Ct)values for amplification of ORF1ab and N genes from individual patients in age-specific groups in a time series.Results:A total of 480 inpatients were included in the study,with a median age of 59 years(interquartile range,42 to 78;range,16 to 106).In the<45-year-old age group,the Ct values for ORF1ab and N gene amplification remained below 35 for 9.0 and 11.5 days,respectively.In the≥80-year-old age group,the Ct values for ORF1ab and N genes stayed below 35 for 11.5 and 15.0 days,respectively,which was the longest among all age groups.The Ct values for N gene amplification took longer to rise above 35 than those for ORF1ab gene amplification.Conclusion:The time to test negative varied among different age groups,with viral nucleic acid shedding taking longer in older age groups compared to younger age groups.As a result,the time to resolution of Omicron infection increased with increasing age.展开更多
基金supported by grants from the National Key Research and Development Project(2022YFE0198100)National Natural Science Foundation of China(32172420)+2 种基金Natural Science Foundation of Jiangsu Province(SBK20220085)Fundamental Research Funds for the Central Universities(KYXK202009,ZJ21195012)the Startup Fund for Distinguished Scholars from Nanjing Agricultural University(to Y.W.).
文摘Pattern-triggered immunity(PTI)and effector-triggered immunity(ETI)are required for host defense against pathogens.Although PTI and ETI are intimately connected,the underlying molecular mechanisms remain elusive.In this study,we demonstrate that flg22 priming attenuates Pseudomonas syringae pv.tomato DC3000(Pst)AvrRpt2-induced hypersensitive cell death,resistance,and biomass reduction in Arabidopsis.Mitogen-activated protein kinases(MAPKs)are key signaling regulators of PTI and ETI.The absence of MPK3 and MPK6 significantly reduces pre-PTI-mediated ETI suppression(PES).We found that MPK3/MPK6 interact with and phosphorylate the downstream transcription factor WRKY18,which regulates the expression of AP2C1 and PP2C5,two genes encoding protein phosphatases.Furthermore,we observed that the PTI-suppressed ETI-triggered cell death,MAPK activation,and growth retardation are significantly attenuated in wrky18/40/60 and ap2c1 pp2c5 mutants.Taken together,our results suggest that the MPK3/MPK6-WRKYs-PP2Cs module underlies PES and is essential for the maintenance of plant fitness during ETI.
基金This work was supported by the National Key Research and Development Project of China(2020YFC0840800)the National Natural Science Foundation of China(no.31801093).
文摘SARS-CoV-2 has caused over 100 million deaths and continues to spread rapidly around the world.Asymptomatic transmission of SARS-CoV-2 is the Achilles’heel of COVID-19 public health control measures.Phylogenomic data on SARS-CoV-2 could provide more direct information about asymptomatic transmission.In this study,using a novel MINERVA sequencing technology,we traced asymptomatic transmission of COVID-19 patients in Beijing,China.One hundred and seventy-eight close contacts were quarantined,and 14 COVID-19 patients were laboratory confirmed by RT-PCR.We provide direct phylogenomic evidence of asymptomatic transmission by constructing the median joining network in the cluster.These data could help us to determine whether the current symptom-based screening should cover asymptomatic persons.
基金Funded by National Key R&D Program of China(2021ZD0114103)the Capital's Funds for Health Improvement and Research(2022-4G-30117)the Beijing Science and Technology Planning Project of Beijing Science and Technology Commission(Z211100002521015 and Z211100002521019).
文摘Introduction:In November 2021,the severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)Omicron variant was identified as the variant of concern and has since spread globally,replacing other cocirculating variants.To better understand the dynamic changes in viral load over time and the natural history of the virus infection,we analyzed the expression of the open reading frames 1ab(ORF1ab)and nucleocapsid(N)genes in patients infected with Omicron.Methods:We included patients initially admitted to the hospital for SARS-CoV-2 infection between November 5 and December 25,2022.We collected daily oropharyngeal swabs for quantitative reverse transcriptase-polymerase chain reaction tests using commercial kits.We depicted the cycle threshold(Ct)values for amplification of ORF1ab and N genes from individual patients in age-specific groups in a time series.Results:A total of 480 inpatients were included in the study,with a median age of 59 years(interquartile range,42 to 78;range,16 to 106).In the<45-year-old age group,the Ct values for ORF1ab and N gene amplification remained below 35 for 9.0 and 11.5 days,respectively.In the≥80-year-old age group,the Ct values for ORF1ab and N genes stayed below 35 for 11.5 and 15.0 days,respectively,which was the longest among all age groups.The Ct values for N gene amplification took longer to rise above 35 than those for ORF1ab gene amplification.Conclusion:The time to test negative varied among different age groups,with viral nucleic acid shedding taking longer in older age groups compared to younger age groups.As a result,the time to resolution of Omicron infection increased with increasing age.
