Calcium-Mediated Abiotic Stress Signaling in Roots

Abstract

Roots are subjected to a range of abiotic stresses as they forage for water and nutrients. Cytosolic free calcium is a common second messenger in the signaling of abiotic stress. In addition, roots take up calcium both as a nutrient and to stimulate exocytosis in growth. For calcium to fulfill its multiple roles must require strict spatio-temporal regulation of its uptake and efflux across the plasma membrane, its buffering in the cytosol and its sequestration or release from internal stores. This prompts the question of how specificity of signaling output can be achieved against the background of calcium’s other uses. Threats to agriculture such as salinity, water availability and hypoxia are signaled through calcium. Nutrient deficiency is also emerging as a stress that is signaled through cytosolic free calcium, with progress in potassium, nitrate and boron deficiency signaling now being made. Heavy metals have the capacity to trigger or modulate root calcium signaling depending on their dose and their capacity to catalyze production of hydroxyl radicals. Mechanical stress and cold stress can both trigger an increase in root cytosolic free calcium, with the possibility of membrane deformation playing a part in initiating the calcium signal. This review addresses progress in identifying the calcium transporting proteins (particularly channels such as annexins and cyclic nucleotide-gated channels) that effect stress-induced calcium increases in roots and explores links to reactive oxygen species, lipid signaling, and the unfolded protein response.

Integrated Analysis of Long Non-coding RNAs (lncRNAs) and mRNAs Reveals the Regulatory Role of lncRNAs Associated With Salt Resistance in Camellia sinensis

“…Thus, in the present study, lncRNAs targeting the eight upregulated GOLS genes may participate in RFO synthesis in response to salt stress. The Ca 2+ signaling pathway was also reported to mediate plant response to salt stress, which starts with Ca 2+ transporters such as Ca 2+ -ATPases, Ca 2+ sensors, and relay proteins such as CaM, CMLs, CDPKs, CBLs, and CIPKs (Wilkins et al, 2016). LncRNAs targeting calcium-transporting ATPase, calmodulin-interacting protein, CDPKs and CIPKs in this study were predicted to be involved in salt-stress response through the Ca 2+ signaling pathway.…”

“…Notably, 42 cis-and 67 trans-target genes were differentially expressed under salt stress. Among these target genes, Ca 2+ -transporting ATPase (TEA027212.1) was reported to be an important gene in Ca 2+ signaling under abiotic stress (Wilkins et al, 2016), which suggests that its corresponding lncRNA, MSTRG.139242.1, may interact with Ca 2+ -transporting ATPase and may be involved in this process. Thus, a gene suppression assay of MSTRG.139242.1 and TEA027212.1 (Ca 2+ -transporting ATPase 13) using AsODNs was conducted and suggested that lncRNA MSTRG.139242.1 may be regulated by its nearby coding gene, TEA027212.1.…”

Oxidative and genotoxic damages in plants in response to heavy metal stress and maintenance of genome stability

“…The rise in the cytosolic Ca 2C in response to Cd 2C has been shown to be due to transportation of external Ca 2C through the Cch1p/Mid1p channel. 42 Based on the dose and the ability for the generation of hydroxyl radicals, the heavy metals regulate calcium in roots.…”

Herbivore exposure alters ion fluxes and improves salt tolerance in a desert shrub

“…Ca 2+ , an important secondary messenger, plays a key role in the plant response to biotic or abiotic stress (Ranty et al, 2016;Wilkins, Matthus, Swarbreck, & Davies, 2016). Extracellular Ca 2+ decreases the K + loss induced by NaCl in Arabidopsis root epidermal protoplasts by blocking K + efflux channels (Shabala et al, 2006); however, it is unknown whether herbivore regulates the Ca 2+ signal during the plant response to NaCl stress.…”

“…Plants have evolved complex strategies to avoid or resist the effects of environmental stresses. Ca 2+ , a ubiquitous secondary messenger and early signalling component, plays essential roles in the plant's defence against both abiotic and biotic stresses (Ranty et al, 2016;Wilkins et al, 2016). The success of the plant's defence response therefore depends on the rapid recognition of stress and the translation of this information into Ca 2+ signals (Santamaria, Arnaiz, Gonzalez-Melendi, Martinez, & Diaz, 2018;Shabala, Wu, & Bose, 2015).…”