Lectin Receptor-Like Kinases: The Sensor and Mediator at the Plant Cell Surface

Abstract

Lectin receptor-like kinases (LecRLKs), a plant-specific receptor-like kinase (RLK) sub-family, have been recently found to play crucial roles in plant development and responses to abiotic and biotic stresses. In this review, we first describe the classification and structures of Lectin RLKs. Then we focus on the analysis of functions of LecRLKs in various biological processes and discuss the status of LecRLKs from the ligands they recognize, substrate they target, signaling pathways they are involved in, to the overall regulation of growth-defense tradeoffs. LecRLKs and the signaling components they interact with constitute recognition and protection systems at the plant cell surface contributing to the detection of environmental changes monitoring plant fitness.

Complex N-Glycans Are Important for Normal Fruit Ripening and Seed Development in Tomato

“…We believe that a different capacity to release N -glycans in the GNTI -RNAi versus the MANII -RNAi lines could be linked to their opposite phenotypes in tomato. Accessibility of the chitobiose part in the GNTI -RNAi lines may additionally modulate growth and developmental readouts, especially concerning apoplastic lectins or receptor-like kinases with a lectin domain (LecRLKs; Bellande et al, 2017 ; Sun et al, 2020 ). In case of the terminal N -glycan parts, lectins with GlcNAc- or mannose-specific domains (WGA- or ConA-type, respectively; Figure 10 ) may compete for binding in MANII -RNAi plants—due to the hybrid N -glycan structure with one branched mannose arm—shared with GNTI -RNAi, and thus differ from wild-type.…”

A G-lectin Receptor Kinase is a Negative Regulator of Arabidopsis Immunity Against Root-Knot Nematode Meloidogyne incognita

“…The best-known members of this group are the S-locus (S-locus glycoprotein/SLG containing) RKs, known for their role in self-incompatibility in flowering plants (Sherman-Broyles et al, 2007; Kusaba et al, 2001). While members of the L-LecRKs have been implicated in defense the G-type LecRKs have not been much explored for their role in immunity and defense (Sun et al, 2020). Our domain analysis identified six distinct domains (G-lectin, SLG, EGF, PAM, TM and kinase) in the ERN1 sequence, which is the largest number of domains identified among the members of this family.…”

“…Several members of the G-LecRK family have been implicated in abiotic stress responses and evidence is starting to emerge as to their roles in biotic stresses (Sun et al, 2020). Both gene expression and mutant analyses indicate positive roles of G-LecRKs in immunity to microbial pathogens as well as to insect pests (Chen et al, 2006; Cheng et al, 2013; Gilardoni et al, 2011; Li et al, 2015; Ranf et al, 2015; Gouhier-Darimont et al, 2019; Sun et al, 2020). In contrast, here we report that the ERN1 G-LecRK is a negative regulator of immunity.…”

LORE receptor homomerization is required for 3-hydroxydecanoic acid-induced immune signaling and determines the natural variation of immunosensitivity within the Arabidopsis genus

“…Apart from SRKs, only a few SD-RLKs from different plant species have been described in more detail. They are involved in plant-pathogen interactions, symbiosis or abiotic stress responses (Navarro-Gochicoa et al, 2003; Chen et al, 2006; Kanzaki et al, 2008; Kim et al, 2009b; Kim et al, 2009a; Gilardoni et al, 2011; Chen et al, 2013; Cheng et al, 2013; Sun et al, 2013a; Zou et al, 2015; Fan et al, 2018; Schnepf et al, 2018; Labbé et al, 2019; Jinjun et al, 2020; Pan et al, 2020; Sun et al, 2020; Liu et al, 2021; Zhou et al, 2021). In Glycine soja , S-LOCUS LecRK ( Gs SRK) regulates osmotic homeostasis and plant architecture under salt stress (Sun et al, 2013a; Sun et al, 2018).…”

“…Biochemical characterization of SD-RLKs and identification of ligands is proving to be particularly challenging. Large-scale expression and purification of SD-RLKs appears to be especially difficult, likely because of their complex folding, high degree of glycosylation, and tendency of protein aggregation (Murase et al, 2020; Sun et al, 2020).…”