Big Roles of Small Kinases: The Complex Functions of Receptor‐Like Cytoplasmic Kinases in Plant Immunity and Development

Abstract

Plants have evolved a large number of receptor-like cytoplasmic kinases (RLCKs) that often functionally and physically associate with receptor-like kinases (RLKs) to modulate plant growth, development and immune responses. Without any apparent extracellular domain, RLCKs relay intracellular signaling often via RLK complex-mediated transphosphorylation events. Recent advances have suggested essential roles of diverse RLCKs in concert with RLKs in regulating various cellular and physiological responses. We summarize here the complex roles of RLCKs in mediating plant immune responses and growth regulation, and discuss specific and overlapping functions of RLCKs in transducing diverse signaling pathways.

Receptor Kinases in Plant-Pathogen Interactions: More Than Pattern Recognition

“…It remains unknown which ubiquitin E3 ligase is responsible for BIK1 turnover and whether this E3 is subject to regulation by CPK28 and the heterotrimeric G protein complex. (Figure 2; Lin et al, 2013a). Among these, BIK1 is a central component integrating signals from multiple PRRs by directly interacting with FLS2, EFR, PEPRs, and CERK1 (Lu et al, 2010;Z.…”

Two redundant receptor-like cytoplasmic kinases function downstream of pattern recognition receptors to regulate activation of SA biosynthesis in Arabidopsis

“…Plants also have a large number of receptor-like cytoplasmic kinases (RLCKs) that are evolutionarily related to RLKs but without a transmembrane domain (Shiu and Bleecker, 2001;Lin et al, 2013). Early studies on the RLCKs Pto and PBS1 implicated these proteins play important roles in plant defense (Martin et al, 1993;Swiderski and Innes, 2001).…”

Signals fly when kinases meet Rho-of-plants (ROP) small G-proteins

“…RLCKs, based on the sequence of their kinase domain, belong to the large receptor-like kinase family. Still, the majority of them do not possess either extracellular receptors or transmembrane domains [91]. RLCKs are classified into several distinct families, including 147 proteins in Arabidopsis and 379 in rice.…”

“…Several of them have been implicated in associating with and transducing signals from receptor-like kinases during a variety of cellular processes, including hormonal and developmental regulation, as well as defence responses [91].…”