Homologous recombination(HR) and nonhomologous end joining(NHEJ) are considered the two main double-strand break(DSB) repair approaches in eukaryotes. Inhibiting the activities of the key component in NHEJ commonly en...Homologous recombination(HR) and nonhomologous end joining(NHEJ) are considered the two main double-strand break(DSB) repair approaches in eukaryotes. Inhibiting the activities of the key component in NHEJ commonly enhances the efficiency of targeted gene knockouts or affects growth and development in higher eukaryotes. However, little is known about the roles of the NHEJ pathway in foliar pathogens. Here we identified a gene designated St KU80, which encodes a putative DNA end-binding protein homologous to yeast Ku80, in the foliar pathogen Exserohilum turcicum. Conserved domain analysis showed that the typical domains VWA, Ku78 and Ku-PK-bind are usually present in Ku70/80 proteins in eukaryotes and are also present in St Ku80. Phylogenetic analysis indicated that St Ku80 is most closely related to Ku80(XP001802136.1) from Parastagonospora nodorum, followed by Ku80(AGF90044.1) from Monascus ruber. Furthermore, the gene knockout mutants ΔSt KU80-1 and ΔSt KU80-2 were obtained. These mutants displayed longer septas, thinner cell walls, smaller amounts of substances on cell wall surfaces, and more mitochondria per cell than the wild-type(WT) strain but similar HT-toxin activity. The mutants did not produce conidia and mature appressoria. On the other hand, the mutants were highly sensitive to H2O2, but not to ultraviolet radiation. In summary, the St KU80 plays devious roles in regulating the development of E. turcicum.展开更多
[ Objective ] This study aimed to investigate the genetic variation of Yunnan Exserohilum turcicum isolates from molecular level, and provide theoretical basis for E. turcicum pathogenicity virulence differentiation a...[ Objective ] This study aimed to investigate the genetic variation of Yunnan Exserohilum turcicum isolates from molecular level, and provide theoretical basis for E. turcicum pathogenicity virulence differentiation and effective control of disease. [Method] A total of 56 E. turc/cum isolates from some areas of Yunnan Province were analyzed by RAPD. Based on the genetic distance, a dendrogram was constructed. [Result] Ten genetic groups were formed in the dendrogram. The RAPD groups had no obvious correlation with geographic origins. Some strains from one area were closely related to some from another area. [ Conclusion] Rich ge- netic variation existed among the tested isolates.展开更多
基金supported by the National Natural Science Foundation of China (31701741 and 31671983)the Natural Science Foundation of Hebei Province,China (C2016204164 and C2019204211)。
文摘Homologous recombination(HR) and nonhomologous end joining(NHEJ) are considered the two main double-strand break(DSB) repair approaches in eukaryotes. Inhibiting the activities of the key component in NHEJ commonly enhances the efficiency of targeted gene knockouts or affects growth and development in higher eukaryotes. However, little is known about the roles of the NHEJ pathway in foliar pathogens. Here we identified a gene designated St KU80, which encodes a putative DNA end-binding protein homologous to yeast Ku80, in the foliar pathogen Exserohilum turcicum. Conserved domain analysis showed that the typical domains VWA, Ku78 and Ku-PK-bind are usually present in Ku70/80 proteins in eukaryotes and are also present in St Ku80. Phylogenetic analysis indicated that St Ku80 is most closely related to Ku80(XP001802136.1) from Parastagonospora nodorum, followed by Ku80(AGF90044.1) from Monascus ruber. Furthermore, the gene knockout mutants ΔSt KU80-1 and ΔSt KU80-2 were obtained. These mutants displayed longer septas, thinner cell walls, smaller amounts of substances on cell wall surfaces, and more mitochondria per cell than the wild-type(WT) strain but similar HT-toxin activity. The mutants did not produce conidia and mature appressoria. On the other hand, the mutants were highly sensitive to H2O2, but not to ultraviolet radiation. In summary, the St KU80 plays devious roles in regulating the development of E. turcicum.
基金Supported by Key Technologies R&D Program of Yunnan Province(2001NG10)
文摘[ Objective ] This study aimed to investigate the genetic variation of Yunnan Exserohilum turcicum isolates from molecular level, and provide theoretical basis for E. turcicum pathogenicity virulence differentiation and effective control of disease. [Method] A total of 56 E. turc/cum isolates from some areas of Yunnan Province were analyzed by RAPD. Based on the genetic distance, a dendrogram was constructed. [Result] Ten genetic groups were formed in the dendrogram. The RAPD groups had no obvious correlation with geographic origins. Some strains from one area were closely related to some from another area. [ Conclusion] Rich ge- netic variation existed among the tested isolates.