Expression of maize calcium‐dependent protein kinase (ZmCPK11) improves salt tolerance in transgenic Arabidopsis plants by regulating sodium and potassium homeostasis and stabilizing photosystem II

Abstract

In plants, CALCIUM‐DEPENDENT PROTEIN KINASES (CDPKs/CPKs) are involved in calcium signaling in response to endogenous and environmental stimuli. Here, we report that ZmCPK11, one of maize CDPKs, participates in salt stress response and tolerance. Salt stress induced expression and upregulated the activity of ZmCPK11 in maize roots and leaves. Activation of ZmCPK11 upon salt stress was also observed in roots and leaves of transgenic Arabidopsis plants expressing ZmCPK11. The transgenic plants showed a long‐root phenotype under control conditions and a short‐root phenotype under NaCl, abscisic acid (ABA) or jasmonic acid (JA) treatment. Analysis of ABA and JA content in roots indicated that ZmCPK11 can mediate root growth by regulating the levels of these phytohormones. Moreover, 4‐week‐old transgenic plants were more tolerant to salinity than the wild‐type plants. Their leaves were less chlorotic and showed weaker symptoms of senescence accompanied by higher chlorophyll content and higher quantum efficiency of photosystem II. The expression of Na+/K+ transporters (HKT1, SOS1 and NHX1) and transcription factors (CBF1, CBF2, CBF3, ZAT6 and ZAT10) with known links to salinity tolerance was upregulated in roots of the transgenic plants upon salt stress. Furthermore, the transgenic plants accumulated less Na+ in roots and leaves under salinity, and showed a higher K+/Na+ ratio in leaves. These results show that the improved salt tolerance in ZmCPK11‐transgenic plants could be due to an upregulation of genes involved in the maintenance of intracellular Na+ and K+ homeostasis and a protection of photosystem II against damage.

The calcium‐dependent protein kinase ZmCDPK7 functions in heat‐stress tolerance in maize

“…CPK8 then phosphorylated CAT3, thus activating CAT3 activity for scavenging H 2 O 2 (Zou et al, 2015). Further, maize CPK11 and CPK4 overexpression in Arabidopsis , and Arabidopsis CPK10 participate in ABA‐mediated signaling and H 2 O 2 homeostasis in the response of Arabidopsis to salt and drought stress (Zou et al, 2010; Jiang et al, 2013; Borkiewicz et al, 2020).…”

“…To date, 40 CDPKs have been identified in maize. Some of these CDPKs respond to various stimuli including salt, drought, cold, abscisic acid (ABA), and H 2 O 2 (Kobayashi et al, 2007; Kong et al, 2013; Xu and Huang, 2017; Borkiewicz et al, 2020). However, limited information is available about which (and how) CDPKs regulate plant responses to heat stress signals.…”

Indole primes defence signalling and increases herbivore resistance in tea plants

“…Therefore, the capacity of indole to prime early defence signalling seems to be a conserved trait in plants early signalling. Given that CDPKs are upstream regulators of JA signalling pathway in many plant species (Borkiewicz et al, 2019; Munemasa, Hossain, Nakamura, Mori, & Murata, 2011; Yang, Hettenhausen, Baldwin, & Wu, 2012), the indole‐induced priming on JA biosynthesis may be achieved through the enhanced Ca 2+ signalling. Apart from these similarities, indole also shows differences in how it modulates plant hormones.…”

Basic Analysis of Calcium-dependent Protein Kinase Gene and Its Closely Related Gene Families in Solanum Pennellii Genome

“…Studies have shown that CDPK and CRK genes were involved in the regulation of root, stem, leaf development, owering, pollen germination, pollen tube growth and seed development 4,21,22,28,[43][44][45][46][47] , as well as in the regulation of gibberellin, auxin, salicylic acid, abscisic acid and methyl jasmonate biosynthesis 27,[48][49][50][51][52][53] . In addition, they also played a role in biological and abiotic stress responses [54][55][56][57][58][59][60][61][62][63][64] . By analyzing the cis-action elements of 2000 bp promoters upstream of SpCDPK and SpCRK family members, we also found that there were a large number of elements related to plant growth and development, hormone induction and stress induction (Figure 7).…”