Pattern Recognition Receptors—Versatile Genetic Tools for Engineering Broad-Spectrum Disease Resistance in Crops

Abstract

Abstract:Infestations of crop plants with pathogens pose a major threat to global food supply. Exploiting plant defense mechanisms to produce disease-resistant crop varieties is an important strategy to control plant diseases in modern plant breeding and can greatly reduce the application of agrochemicals. The discovery of different types of immune receptors and a detailed understanding of their activation and regulation mechanisms in the last decades has paved the way for the deployment of these central plant immune components for genetic plant disease management. This review will focus on a particular class of immune sensors, termed pattern recognition receptors (PRRs), that activate a defense program termed pattern-triggered immunity (PTI) and outline their potential to provide broad-spectrum and potentially durable disease resistance in various crop species-simply by providing plants with enhanced capacities to detect invaders and to rapidly launch their natural defense program.

The Arabidopsis leucine-rich repeat receptor kinase MIK2 is a crucial component of pattern-triggered immunity responses to Fusarium fungi

“…Finally, there are several examples of successful transfer of PRRs to enhance disease resistance (Lacombe et al 2010; Schoonbeek et al 2015). PRRs or other components found in Arabidopsis might be transferred to crops or recombined with crop genes to link up with endogenous immune components and thereby engineer durable and broad-spectrum resistance (Ranf 2018). Indeed, MIK2 has many homologs in diverse crop plants, which may ease comparative genomics between model and crop towards interspecies functional complementation of Fusarium resistance.…”

Prospects of Gene Knockouts in the Functional Study of MAMP-Triggered Immunity: A Review

“…Microbes that evade these barriers are confronted by an innate immune system, since plants lack adaptive immunity [6][7][8]. The primary defence response of plants is achieved through the perception of conserved signatures referred to as microbe-associated molecular patterns (MAMPs) by pattern recognition receptors (PRRs), localised in the plasma membrane, which leads to MAMP-triggered immunity (MTI) [8,9] (Figure 1). These plant PRRs mostly belong to the receptor-like kinase (RLKs) or receptor-like protein (RLPs) families.…”

“…These plant PRRs mostly belong to the receptor-like kinase (RLKs) or receptor-like protein (RLPs) families. In this regard, RLKs contain an extracellular ligand-binding ectodomain, a transmembrane domain, and an intracellular serine/threonine (Ser/Thr) kinase domain [8][9][10]. The RLPs, on the other hand, have a similar architecture, but lack the intracellular protein kinase domain [9].…”

“…In this regard, RLKs contain an extracellular ligand-binding ectodomain, a transmembrane domain, and an intracellular serine/threonine (Ser/Thr) kinase domain [8][9][10]. The RLPs, on the other hand, have a similar architecture, but lack the intracellular protein kinase domain [9]. The cytoplasmic receptor-like kinases (RLCKs) are not able to perceive MAMPs, because they lack an extracellular domain, but can interact with RLKs and participate in phosphorylation cascades, thereby leading to the activation of downstream innate immune response [8,9,11].…”

“…RLKs and RLPs are classified into subfamilies, depending on the motifs or domains of the ectodomains [36]. These domains include leucine-rich repeat (LRR), lysin M (LysM) or lectin (Lec), used to bind specifically to ligands [9,80]. A number of RLKs and RLPs use LRRs to bind MAMP epitopes.…”