CDPKs in immune and stress signaling

Abstract

Ca2+ has long been recognized as a conserved second messenger and principal mediator in plant immune and stress responses. How Ca2+ signals are sensed and relayed into diverse primary and global signaling events is still largely unknown. Comprehensive analyses of the plant-specific multigene family of Ca2+-dependent protein kinases (CDPKs) are unraveling the molecular, cellular and genetic mechanisms of Ca2+ signaling. CDPKs, which exhibit overlapping and distinct expression patterns, sub-cellular localizations, substrate specificities and Ca2+ sensitivities, play versatile roles in the activation and repression of enzymes, channels and transcription factors. Here, we review the recent advances on the multifaceted functions of CDPKs in the complex immune and stress signaling networks, including oxidative burst, stomatal movements, hormonal signaling and gene regulation.

Harnessing host ROS-generating machinery for the robust genome replication of a plant RNA virus

“…Our previous proteomics analysis showed that NbCDPKiso2 was present in the affinity-purified fraction of RCNMV replication complex (29). CDPK is a calcium sensor protein and comprises a multigene family (e.g., 34 members in A. thaliana and 29 members in tomato), which is divided into four subgroups (38)(39)(40). Phylogenetic analysis revealed that NbCDPKiso2 belongs to subgroup II CDPK (Fig.…”

“…Tobacco CDPK1 (NtCDPK1), a close relative of NbCDPKiso2, regulates the function of a transcription factor in response to a phytohormone, gibberellin (41). Interestingly, it has been proposed that A. thaliana subgroup II CDPK (AtCPK3) may be involved in MAMP responses (38). Furthermore, it is known that some isoforms of CDPK phosphorylate and activate RBOH (13)(14)(15).…”

“…Each CDPK consists of a kinase domain, an autoinhibitory pseudosubstrate domain, multiple Ca 2+ -binding EF-hand motifs, and an N-terminal variable domain (V domain) (38). It is proposed that the V domain determines the substrate specificity of CDPKs (42,43).…”

Genome-wide analysis and expression profiling of calcium-dependent protein kinases in potato (Solanum tuberosum)

“…Because the previously identified StCDPK3 and StCDPK5 are absent from these bases, we used for further analyses StCDPK3 (cDNA and genomic) and StCDPK5 (cDNA) sequences deposited in GenBank (NCBI). Altogether, 23 potato CDPKs were identified, designated StCPK1 -StCPK23 according to the proposed nomenclature for CDPK genes (Hrabak et al 1996;Boudsocq and Sheen 2013) (Table 1 and Supplementary material 1). The CDPK genes are indicated by the three-letter abbreviation CPK followed by a number.…”

“…Thus, tomato LeCDPK2 regulates ethylene biosynthesis in response to wound signalling (Kamiyoshihara et al 2010); Arabidopsis AtCPK1/2/4/5/11 phosphorylate and thereby activate NADPH oxidase to promote reactive oxygen species (ROS) production in response to abiotic and biotic stimuli (Gao et al 2013); rice OsCPK4 participates in rice tolerance to salt and drought stress by protecting cellular membranes from lipid peroxidation (Campo et al 2014), grapevine gene VaCPK29 confers tolerance to heat and osmotic stresses (Dubrovina et al 2017), whereas ZmCPK11 is involved in touch-and wound-induced pathways in maize (Szczegielniak et al 2012). CDPKs are widely involved in various types of disease resistance (Boudsocq et al 2010;Boudsocq and Sheen 2013;Romeis and Herde 2014;Wang et al 2015). They regulate the plants' defence response locally and also systemically (Romeis and Herde 2014).…”