Plant fungal pathogens secrete numerous proteins into the apoplast at the plant–fungus contact sites to facilitate colonization.However,only a few secretory proteins were functionally characterized in Magnaporthe ory...Plant fungal pathogens secrete numerous proteins into the apoplast at the plant–fungus contact sites to facilitate colonization.However,only a few secretory proteins were functionally characterized in Magnaporthe oryzae,the fungal pathogen causing rice blast disease worldwide.Asparagine-linked glycosylation 3(Alg3)is an a-1,3-mannosyltransferase functioning in the Nglycan synthesis of N-glycosylated secretory proteins.Fungal pathogenicity and cell wall integrity are impaired inΔalg3 mutants,but the secreted proteins affected inΔalg3 mutants are largely unknown.In this study,we compared the secretomes of the wild-type strain and theΔalg3 mutant and identified 51 proteins that require Alg3 for proper secretion.These proteins were predicted to be involved in metabolic processes,interspecies interactions,cell wall organization,and response to chemicals.Nine proteins were selected for further validation.We found that these proteins were localized at the apoplastic region surrounding the fungal infection hyphae.Moreover,the Nglycosylation of these proteins was significantly changed in theΔalg3 mutant,leading to the decreased protein secretion and abnormal protein localization.Furthermore,we tested the biological functions of two genes,INV1(encoding invertase 1,a secreted invertase)and AMCase(encoding acid mammalian chinitase,a secreted chitinase).The fungal virulence was significantly reduced,and the cell wall integrity was altered in theΔinv1 andΔamcase mutant strains.Moreover,the N-glycosylation was essential for the function and secretion of AMCase.Taken together,our study provides new insight into the role of N-glycosylated secretory proteins in fungal virulence and cell wall integrity.展开更多
Aim:The aim was to investigate the infectious conditions of Epstein-Barr virus(EBV)in patients with multiple sclerosis(MS).Methods:Cerebrospinal fluid(CSF)of 20 patients with MS and 20 with other neurological diseases...Aim:The aim was to investigate the infectious conditions of Epstein-Barr virus(EBV)in patients with multiple sclerosis(MS).Methods:Cerebrospinal fluid(CSF)of 20 patients with MS and 20 with other neurological diseases(OND)were tested with indirect immunofluorescence for anti-EBV capsid antigen(EBV-CA)immunoglobulin G(IgG),IgG affinity for anti-EBV-CA,anti-EBV-CA immunoglobulin M(IgM),anti-EBV early antigen(EBV-EA)IgG and anti-EBV nuclear antigen(EBNA)IgG.According to the pattern of antibodies in CSF,infection rates of acute,chronic,primary,recurrent,and past infections were analyzed in the two groups of patients.Results:There were no significant differences in anti-EBV-CA,anti-EBC-EA,and anti-EBNA antigen IgG in CSF between MS and OND patients(P>0.05).The positive rate of low affinity for anti-EBV-CA IgG in MS patients was significantly higher than that for OND patients(75%vs.40%,P<0.05).Furthermore,significant differences in the positive rate of anti-EBV-CA IgM were found between MS and OND patients(70%vs.25%,P<0.05).Of the MS patients,75%were in an EBV acute infection state compared with 40%of OND patients(P<0.05).Conclusion:Acute infection of EBV closely correlates with the occurrence of MS.展开更多
基金supported by the National Key R&D Plan of China(Grant No.2016YFD0300703)the China Agricultural Research System(Grant No.CARS-01-33)+2 种基金the Program for Changjiang Scholars and Innovative Research Team in University(Grant No.IRT1042)the 111 Project(Grant No.B13006)to YLPthe National Natural Science Foundation of China(Grant No.32001848)to XL。
文摘Plant fungal pathogens secrete numerous proteins into the apoplast at the plant–fungus contact sites to facilitate colonization.However,only a few secretory proteins were functionally characterized in Magnaporthe oryzae,the fungal pathogen causing rice blast disease worldwide.Asparagine-linked glycosylation 3(Alg3)is an a-1,3-mannosyltransferase functioning in the Nglycan synthesis of N-glycosylated secretory proteins.Fungal pathogenicity and cell wall integrity are impaired inΔalg3 mutants,but the secreted proteins affected inΔalg3 mutants are largely unknown.In this study,we compared the secretomes of the wild-type strain and theΔalg3 mutant and identified 51 proteins that require Alg3 for proper secretion.These proteins were predicted to be involved in metabolic processes,interspecies interactions,cell wall organization,and response to chemicals.Nine proteins were selected for further validation.We found that these proteins were localized at the apoplastic region surrounding the fungal infection hyphae.Moreover,the Nglycosylation of these proteins was significantly changed in theΔalg3 mutant,leading to the decreased protein secretion and abnormal protein localization.Furthermore,we tested the biological functions of two genes,INV1(encoding invertase 1,a secreted invertase)and AMCase(encoding acid mammalian chinitase,a secreted chitinase).The fungal virulence was significantly reduced,and the cell wall integrity was altered in theΔinv1 andΔamcase mutant strains.Moreover,the N-glycosylation was essential for the function and secretion of AMCase.Taken together,our study provides new insight into the role of N-glycosylated secretory proteins in fungal virulence and cell wall integrity.
基金The work was supported by Beijing Natural Science Foundation(Nos.7102040,7132060)National Natural Science Foundation of China(Nos.81041020,81271311 and 81241039)+2 种基金Traditional Chinese Medicine,Beijing Technology Development Fund(No.SF-2007-III-22),Beijing Excellent Talent Foundation(No.20071-D0300100062)the high-level technical training project funding of the Beijing health system(2011-3-004)the preferential funding scheme for Beijing city staff to go abroad.Conflict of Interest:No.
文摘Aim:The aim was to investigate the infectious conditions of Epstein-Barr virus(EBV)in patients with multiple sclerosis(MS).Methods:Cerebrospinal fluid(CSF)of 20 patients with MS and 20 with other neurological diseases(OND)were tested with indirect immunofluorescence for anti-EBV capsid antigen(EBV-CA)immunoglobulin G(IgG),IgG affinity for anti-EBV-CA,anti-EBV-CA immunoglobulin M(IgM),anti-EBV early antigen(EBV-EA)IgG and anti-EBV nuclear antigen(EBNA)IgG.According to the pattern of antibodies in CSF,infection rates of acute,chronic,primary,recurrent,and past infections were analyzed in the two groups of patients.Results:There were no significant differences in anti-EBV-CA,anti-EBC-EA,and anti-EBNA antigen IgG in CSF between MS and OND patients(P>0.05).The positive rate of low affinity for anti-EBV-CA IgG in MS patients was significantly higher than that for OND patients(75%vs.40%,P<0.05).Furthermore,significant differences in the positive rate of anti-EBV-CA IgM were found between MS and OND patients(70%vs.25%,P<0.05).Of the MS patients,75%were in an EBV acute infection state compared with 40%of OND patients(P<0.05).Conclusion:Acute infection of EBV closely correlates with the occurrence of MS.