Yuan Meng, Ke Yinggen, Huang Renyan, Ma Ling, Yang Zeyu, Chu Zhaohui, Xiao Jinghua, Li Xianghua, Wang Shiping
National Key Laboratory of Crop Genetic Improvement, National Center of Plant Gene Research (Wuhan), Huazhong Agricultural University, Wuhan, China.
State Key Laboratory of Crop Biology, Shandong Provincial Key Laboratory of Agricultural Microbiology, Shandong Agricultural University, Taian, China.
Elife. 2016 Jul 29;5:e19605. doi: 10.7554/eLife.19605.
Transcription activator-like effectors (TALEs) are sequence-specific DNA binding proteins found in a range of plant pathogenic bacteria, where they play important roles in host-pathogen interactions. However, it has been unclear how TALEs, after they have been injected into the host cells, activate transcription of host genes required for infection success. Here, we show that the basal transcription factor IIA gamma subunit TFIIAγ5 from rice is a key component for infection by the TALE-carrying bacterium Xanthomonas oryzae pv. oryzae, the causal agent for bacterial blight. Direct interaction of several TALEs with TFIIAγ5 is required for activation of disease susceptibility genes. Conversely, reduced expression of the TFIIAγ5 host gene limits the induction of susceptibility genes and thus decreases bacterial blight symptoms. Suppression or mutation of TFIIAγ5 can also reduce bacterial streak, another devastating disease of rice caused by TALE-carrying X. oryzae pv. oryzicola. These results have important implications for formulating a widely applicable strategy with which to improve resistance of plants to TALE-carrying pathogens.
转录激活样效应因子（TALEs）是一类在多种植物致病细菌中发现的序列特异性DNA结合蛋白，它们在宿主与病原体的相互作用中发挥着重要作用。然而，尚不清楚TALEs在被注入宿主细胞后是如何激活感染成功所需的宿主基因转录的。在此，我们表明水稻的基础转录因子IIAγ亚基TFIIAγ5是携带TALE的细菌——水稻白叶枯病菌（引起水稻白叶枯病的病原体）感染的关键成分。几种TALEs与TFIIAγ5的直接相互作用是激活感病基因所必需的。相反，TFIIAγ5宿主基因表达的降低会限制感病基因的诱导，从而减轻水稻白叶枯病症状。TFIIAγ5的抑制或突变也可以减轻细菌性条斑病症状，细菌性条斑病是由携带TALE的水稻条斑病菌引起的另一种毁灭性水稻病害。这些结果对于制定一种广泛适用的策略以提高植物对携带TALE的病原体的抗性具有重要意义。
