Pathogen perception and signaling in plant immunity

Abstract

Plant diseases are a constant and serious threat to agriculture and ecological biodiversity. Plants possess a sophisticated innate immunity system capable of detecting and responding to pathogen infection to prevent disease. Our understanding of this system has grown enormously over the past century. Early genetic descriptions of plant disease resistance and pathogen virulence were embodied in the gene-for-gene hypothesis, while physiological studies identified pathogen-derived elicitors that could trigger defense responses in plant cells and tissues. Molecular studies of these phenomena have now coalesced into an integrated model of plant immunity involving cell surface and intracellular detection of specific pathogen-derived molecules and proteins culminating in the induction of various cellular responses. Extracellular and intracellular receptors engage distinct signaling processes but converge on many similar outputs with substantial evidence now for integration of these pathways into interdependent networks controlling disease outcomes. Many of the molecular details of pathogen recognition and signaling processes are now known, providing opportunities for bioengineering to enhance plant protection from disease. Here we provide an overview of the current understanding of the main principles of plant immunity, with an emphasis on the key scientific milestones leading to these insights.

Atlas of tandem kinase proteins across the plant kingdom

“…Another possible hypothesis for the activation of tandem kinases recognition of the effector occurs via integrated non-kinase domains. Like in NLR-ID receptors, the integration is the decoy domain, which mimics pathogen effector targets, and allows for direct interception of effector pathogen proteins 10 . Recently, two TKPs (WTK6-vWA and WTK6b-vWA) were demonstrated to include an integrated domain 19,21 .…”

“…Beta lectin (Legume lectin domain; PF00139) is a carbohydrate-binding domain often found in proteins involved in plant defense reactions, such as chitinases, glucanases, and thaumatins [24][25][26] . The functions of the LRR VIII domain are poorly understood, but LRR domains are associated with plant immune responses, often found in immune receptors like LRR-RLKs 10 . Another signi cant ID identi ed in NLR proteins is the HMA domain.…”

“…Downstream signaling of PRRs and NLRs overlaps and mutually potentiates each other, despite having differing structural characteristics and identifying different pathogen components. The activation of plant immune receptors triggers a series of responses: release of calcium, an elevation in reactive oxygen species, the activation of MAP kinases, and alterations in gene transcription geared towards defense 10 .…”

Celebrating the American Society of Plant Biologists centennial anniversary: A compendium of review articles in plant biology

“…In “Cytokinin: From autoclaved DNA to two-component signaling,” Argueso and Kieber (2024) review cytokinin function, metabolism, transport, and the nature of cytokinin 2-component signaling pathways. Spoel and Dong (2024) review the major plant defense hormone salicylic acid and its crosstalk with other phytohormones in “Salicylic acid in plant immunity and beyond.” Dodds et al (2024) review some of the major themes in plant immunity in “Pathogen perception and signaling in plant immunity,” including the gene-for-gene hypothesis, nucleotide-binding/leucine-rich-repeat receptor (NLR) receptors, pattern-triggered and effector-triggered immunity, and efforts in NLR engineering. In “Nitrogen sensing and regulatory networks: It's about time and space,” Shanks et al (2024) focus on temporal and spatial aspects of nitrogen sensing and signaling and discuss efforts to improve nitrogen-use efficiency in crops.…”

Celebrating the American Society of Plant Biologists centennial anniversary: A compendium of review articles in plant biology

“… Spoel and Dong (2024) review the major plant defense hormone salicylic acid and its crosstalk with other phytohormones in Salicylic acid in plant immunity and beyond . Dodds et al (2024) review some of the major themes in plant immunity in Pathogen perception and signaling in plant immunity , including the gene-for-gene hypothesis, nucleotide-binding/leucine-rich-repeat receptor (NLR) receptors, pattern-triggered and effector-triggered immunity, and efforts in NLR engineering. In Nitrogen sensing and regulatory networks: It's about time and space , Shanks et al (2024) focus on temporal and spatial aspects of nitrogen sensing and signaling and discuss efforts to improve nitrogen-use efficiency in crops.…”