A Calcium/Calmodulin-regulated Member of the Receptor-like Kinase Family Confers Cold Tolerance in Plants

Abstract

Cold is a limiting environmental factor that adversely affects plant growth and productivity. Calcium/calmodulinmediated signaling is believed to play a pivotal role in plant response to cold stress, but its exact role is not clearly understood. Here, we report that CRLK1, a novel calcium/calmodulin-regulated receptor-like kinase, is crucial for cold tolerance in plants. CRLK1 has two calmodulin-binding sites with different affinities as follows: one located at residues 369 -390 with a K d of 25 nM, and the other located at residues 28 -112 with a K d of 160 nM. Calcium/calmodulin stimulated the kinase activity, but the addition of chlorpromazine, a calmodulin antagonist, blocked its stimulation. CRLK1 is mainly localized in the plasma membrane, and its expression is stimulated by cold and hydrogen peroxide treatments. Under normal growth conditions, there is no noticeable phenotypic difference between wild-type and crlk1 knock-out mutant plants. However, as compared with wild-type plants, the crlk1 knock-out mutants exhibited an increased sensitivity to chilling and freezing temperatures. Northern analysis showed that the induction of cold-responsive genes, including CBF1, RD29A, COR15a, and KIN1 in crlk1 mutants, is delayed as compared with wild-type plants. These results indicate that CRLK1 is a positive regulator of cold tolerance in plants. Furthermore, our results suggest that CRLK1 plays a role in bridging calcium/calmodulin signaling and cold signaling.

Coping with Stresses: Roles of Calcium- and Calcium/Calmodulin-Regulated Gene Expression

“…An indirect regulation of cold acclimation by Ca 2+ /CaM was revealed in a study of a Ca 2+ /CaM-regulated receptor kinase CRLK1 (Yang et al, 2010b). Ca 2+ /CaM binding to CRLK1 upregulates its activity.…”

Recent Advances in Calcium/Calmodulin-Mediated Signaling with an Emphasis on Plant-Microbe Interactions

“…-mediated signals could regulate a broad range of physiological activities related to plant growth, development, and responses to environmental stimuli (Zhang et al, 2002;Vanoosthuyse et al, 2003;Charpenteau et al, 2004;Hua et al, 2004;Liu et al, 2008;Kim et al, 2009a;Yang et al, 2010;Oh et al, 2012). Among all these CaM-regulated kinases, CCaMK has been widely studied because of its role in symbioses, developmental processes, and stress responses.…”

“…Some RLKs from plants contain only a kinase domain and thus are named receptor-like cytoplasmic kinases. Some receptor-like cytoplasmic kinases, such as CRCK1 and homologs (Yang et al, 2004), and RLKs, such as SRK, CaM-binding receptor-like kinase, AtCaMRLK, AtCRLK1, and BRI1, are CaM-binding proteins (Vanoosthuyse et al, 2003;Charpenteau et al, 2004;Kim et al, 2009a;DeFalco et al, 2010b;Yang et al, 2010;Oh et al, 2012). Last but not least, some of the mitogen-activated protein kinases (MAPKs), specifically members of Moon et al (2005) subgroup D of MAPK in Arabidopsis and rice (Oryza sativa), were reported to be regulated by Ca 2+ /CaM (Ding et al, 2009;Takahashi et al, 2011).…”

HIGH EXPRESSION OF OSMOTICALLY RESPONSIVE GENES1 Is Required for Circadian Periodicity through the Promotion of Nucleo-Cytoplasmic mRNA Export in Arabidopsis

“…The CBF proteins bind to characterized cis-elements in cold-responsive genes to alter their expression and induce pathways enabling cold survival (Stockinger et al, 1997;Gilmour et al, 1998). Cold signaling can also affect CBF transcription through calcium signaling (Yang et al, 2010) and calmodulin-binding transcription factor activity (Doherty et al, 2009).…”