Cleavage and nuclear localization of the rice XA21 immune receptor

10.015
Chang-Jin Park, Pamela C. Ronald
Nature Communications, 2012, 3(6): 920  DOI: 10.1038/ncomms1932     追溯原文......本站官方QQ群:62473826

Plants and animals carry specific receptors that recognize invading pathogens and respond by activating an immune response. The rice XA21 receptor confers broad-spectrum immunity to the Gram-negative bacterial pathogen, Xanthomonas oryzae pv. oryzae upon recognition of a small protein, Ax21, that is conserved in all Xanthomonas species and related genera. Here we demonstrate that XA21 is cleaved to release the intracellular kinase domain and that this intracellular domain carries a functional nuclear localization sequence. Bimolecular fluorescence complementation assays indicate that the XA21 intracellular domain interacts with the OsWRKY62 transcriptional regulator exclusively in the nucleus of rice protoplasts. In vivo cleavage of XA21 and translocalization of the intracellular kinase domain to the nucleus is required for the XA21-mediated immune response. These results suggest a new model for immune receptor function: on receptor recognition of conserved microbial signatures, the associated kinase translocates to the nucleus where it directly interacts with transcriptional regulators.

水稻XA21免疫受体的剪切和细胞核定位

动植物具有特异的受体识别病原菌的入侵,并通过激活免疫反应对病原菌进行应答。水稻XA21受体可以识别Xanthomonas及相关属中保守的Ax21小蛋白,从而对革兰氏阴性菌白叶枯病菌具有广谱抗性。这里我们证明了XA21通过剪切释放出胞内激酶结构域,该胞内激酶结构域包含一个功能性细胞核定位序列。双分子荧光互补分析表明在水稻原生质体细胞核中,XA21胞内结构域与OsWRKY62转录调节子互作。XA21在体内的剪切以及胞内激酶结构域的定位转移对XA21介导的免疫应答是必需的。这些结果表明一种新的免疫受体作用模式:受体识别保守的微生物特征标签,相关激酶转移到细胞核中直接与转录调节子相互作用。


基因列表
  白叶枯病抗性基因 Xa21; Xa-21
  WRKY转录因子 OsWRKY62