Plants deploy cell-surface and intracellular leucine rich-repeat domain (LRR) immune receptors to detect pathogens¹. LRR receptor kinases and LRR receptor proteins at the plasma membrane recognize microorganism-derived molecules to elicit pattern-triggered immunity (PTI), whereas nucleotide-binding LRR proteins detect microbial effectors inside cells to confer effector-triggered immunity (ETI). Although PTI and ETI are initiated in different host cell compartments, they rely on the transcriptional activation of similar sets of genes², suggesting pathway convergence upstream of nuclear events. Here we report that PTI triggered by the Arabidopsis LRR receptor protein RLP23 requires signalling-competent dimers of the lipase-like proteins EDS1 and PAD4, and of ADR1 family helper nucleotide-binding LRRs, which are all components of ETI. The cell-surface LRR receptor kinase SOBIR1 links RLP23 with EDS1, PAD4 and ADR1 proteins, suggesting the formation of supramolecular complexes containing PTI receptors and transducers at the inner side of the plasma membrane. We detected similar evolutionary patterns in LRR receptor protein and nucleotide-binding LRR genes across Arabidopsis accessions; overall higher levels of variation in LRR receptor proteins than in LRR receptor kinases are consistent with distinct roles of these two receptor families in plant immunity. We propose that the EDS1–PAD4–ADR1 node is a convergence point for defence signalling cascades, activated by both surface-resident and intracellular LRR receptors, in conferring pathogen immunity.

植物利用细胞表面和细胞内富含亮氨酸重复结构域 (LRR) 的免疫受体来检测病原体¹。质膜上的 LRR 受体激酶和 LRR 受体蛋白识别微生物衍生分子以引发模式触发免疫 (PTI)，而核苷酸结合 LRR 蛋白检测细胞内的微生物效应物以赋予效应物触发免疫 (ETI)。虽然 PTI 和 ETI 是在不同的宿主细胞区室中启动的，但它们依赖于相似基因组²的转录激活，这表明核事件上游的通路会聚。在这里，我们报告拟南芥引发的 PTILRR 受体蛋白 RLP23 需要脂肪酶样蛋白 EDS1 和 PAD4 以及 ADR1 家族辅助核苷酸结合 LRR 的信号传导能力二聚体，它们都是 ETI 的组成部分。细胞表面 LRR 受体激酶 SOBIR1 将 RLP23 与 EDS1、PAD4 和 ADR1 蛋白连接起来，表明在质膜内侧形成了含有 PTI 受体和转导物的超分子复合物。我们在整个拟南芥中检测到 LRR 受体蛋白和核苷酸结合 LRR 基因的相似进化模式加入；LRR 受体蛋白的整体变异水平高于 LRR 受体激酶，这与这两个受体家族在植物免疫中的不同作用一致。我们提出 EDS1–PAD4–ADR1 节点是防御信号级联的汇聚点，由表面驻留和细胞内 LRR 受体激活，赋予病原体免疫力。