核苷酸结合和富含亮氨酸的重复受体(NLR)是细胞内植物免疫受体,可识别分泌到植物细胞中的病原体效应子。典型的NLR通常包含三个保守域,包括中央核苷酸结合(NB-ARC)域,C端富含亮氨酸的重复(LRR)和N端结构域。植物NLR的亚家族含有另外的非规范结构域,其潜在地从规范NLR结构中的效应物靶标的整合进化而来。因此,这些具有额外域的NLR被称为具有整合域的NLR(NLR-ID)。这里,我们首先总结了我们目前对效应子结合后NLR-ID激活的理解,重点关注NLR对Pik-1/Pik-2,RGA4/RGA5和RRS1/RPS4。正如最近在某些规范植物NLR中显示的那样,我们推测了它们潜在的寡聚化成抗性体。此外,我们讨论了我们对NLR-ID作用模式的日益深入的了解如何在快速进化的病原体的背景下不断为设计新的抗性特异性的工程方法提供信息.
Nucleotide-binding and leucine-rich repeat receptors (NLRs) are intracellular plant immune receptors that recognize pathogen effectors secreted into the plant cell. Canonical NLRs typically contain three conserved domains including a central nucleotide binding (NB-ARC) domain, C-terminal leucine-rich repeats (LRRs) and an N-terminal domain. A subfamily of plant NLRs contain additional noncanonical domain(s) that have potentially evolved from the integration of the effector targets in the canonical NLR structure. These NLRs with extra domains are thus referred to as NLRs with integrated domains (NLR-IDs). Here, we first summarize our current understanding of NLR-ID activation upon effector binding, focusing on the NLR pairs Pik-1/Pik-2, RGA4/RGA5, and RRS1/RPS4. We speculate on their potential oligomerization into resistosomes as it was recently shown for certain canonical plant NLRs. Furthermore, we discuss how our growing understanding of the mode of action of NLR-ID continuously informs engineering approaches to design new resistance specificities in the context of rapidly evolving pathogens.