Table_5_Evolution of the Genes Encoding Effector Candidates Within Multiple Pathotypes of Magnaporthe oryzae.xlsx

Magnaporthe oryzae infects rice, wheat, and many grass species in the Poaceae family by secreting protein effectors. Here, we analyzed the distribution, sequence variation, and genomic context of effector candidate (EFC) genes in 31 isolates that represent five pathotypes of M. oryzae, three isolates of M. grisea, a sister species of M. oryzae, and one strain each for eight species in the family Magnaporthaceae to investigate how the host range expansion of M. oryzae has likely affected the evolution of effectors. We used the EFC genes of M. oryzae strain 70-15, whose genome has served as a reference for many comparative genomics analyses, to identify their homologs in these strains. We also analyzed the previously characterized avirulence (AVR) genes and single-copy orthologous (SCO) genes in these strains, which showed that the EFC and AVR genes evolved faster than the SCO genes. The EFC and AVR repertoires among M. oryzae pathotypes varied widely probably because adaptation to individual hosts exerted different types of selection pressure. Repetitive DNA elements appeared to have caused the variation of some EFC genes. Lastly, we analyzed expression patterns of the AVR and EFC genes to test the hypothesis that such genes are preferentially expressed during host infection. This comprehensive dataset serves as a foundation for future studies on the genetic basis of the evolution and host specialization in M. oryzae.稻瘟病菌（Magnaporthe oryzae）可通过分泌蛋白质效应子侵染水稻、小麦及禾本科（Poaceae）的多种草本物种。本研究针对31株代表稻瘟病菌5种致病型的分离株、3株稻瘟病菌姊妹物种灰梨孢（M. grisea）分离株，以及巨壳科（Magnaporthaceae）8个物种各1株的菌株，分析了其中效应子候选（effector candidate, EFC）基因的分布、序列变异及基因组背景，以探究稻瘟病菌的宿主范围扩张可能对效应子演化产生的影响。 本研究以基因组已作为诸多比较基因组学分析参考序列的稻瘟病菌菌株70-15的EFC基因为参照，在上述菌株中鉴定其同源基因。此外，本研究还分析了这些菌株中已被表征的无毒（avirulence, AVR）基因与单拷贝同源（single-copy orthologous, SCO）基因，结果显示EFC基因与AVR基因的演化速率显著快于SCO基因。 稻瘟病菌不同致病型间的EFC与AVR基因库差异显著，这大概率是因为适配不同宿主的过程施加了不同类型的选择压力。重复DNA元件似乎是部分EFC基因产生序列变异的诱因。最后，本研究分析了AVR与EFC基因的表达模式，以验证这类基因在宿主侵染阶段优先表达的假说。本综合数据集可为未来探究稻瘟病菌演化与宿主特化的遗传基础提供重要支撑。