StKU80, a component in the NHEJ repair pathway, is involved in mycelial morphogenesis, conidiation, appressorium development, and oxidative stress reactions in Exserohilum turcicum  

作　　者：GONG Xiao-dong LIU Yu-wei BI Huan-huan YANG Xiao-rong HAN Jian-min DONG Jin-gao GU Shou-qin 

机构地区：[1]State Key Laboratory of North China Crop Improvement and Regulation/Key Laboratory of Hebei Province for Plant Physiology and Molecular Pathology,College of Life Sciences,Hebei Agricultural University,Baoding 071001,P.R.China [2]College of Plant Protection,Hebei Agricultural University,Baoding 071001,P.R.China [3]Botou Vocational College,Cangzhou 062150,P.R.China

出　　处：《Journal of Integrative Agriculture》2021年第1期147-158,共12页农业科学学报（英文版）

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)。

摘　　要：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.

关 键 词：Exserohilum turcicum PATHOGENICITY gene knockout growth and development 

分 类 号：S432[农业科学—植物病理学]