Arabidopsis transcriptional response to extracellular Ca²⁺ depletion involves a transient rise in cytosolic Ca²⁺

Abstract

Ecological evidence indicates a worldwide trend of dramatically decreased soil Ca(2+) levels caused by increased acid deposition and massive timber harvesting. Little is known about the genetic and cellular mechanism of plants' responses to Ca(2+) depletion. In this study, transcriptional profiling analysis helped identify multiple extracellular Ca(2+) ([Ca(2+) ]ext ) depletion-responsive genes in Arabidopsis thaliana L., many of which are involved in response to other environmental stresses. Interestingly, a group of genes encoding putative cytosolic Ca(2+) ([Ca(2+) ]cyt ) sensors were significantly upregulated, implying that [Ca(2+) ]cyt has a role in sensing [Ca(2+) ]ext depletion. Consistent with this observation, [Ca(2+) ]ext depletion stimulated a transient rise in [Ca(2+) ]cyt that was negatively influenced by [K(+) ]ext , suggesting the involvement of a membrane potential-sensitive component. The [Ca(2+) ]cyt response to [Ca(2+) ]ext depletion was significantly desensitized after the initial treatment, which is typical of a receptor-mediated signaling event. The response was insensitive to an animal Ca(2+) sensor antagonist, but was suppressed by neomycin, an inhibitor of phospholipase C. Gd(3+) , an inhibitor of Ca(2+) channels, suppressed the [Ca(2+) ]ext -triggered rise in [Ca(2+) ]cyt and downstream changes in gene expression. Taken together, this study demonstrates that [Ca(2+) ]cyt plays an important role in the putative receptor-mediated cellular and transcriptional response to [Ca(2+) ]ext depletion of plant cells.

The Roles of CCCH Zinc-Finger Proteins in Plant Abiotic Stress Tolerance

“…Plants rapidly respond to a specific abiotic stress based on which type of sensor is stimulated, as this determines which series of responses is activated [ 193 , 194 ]. For instance, the sphingolipid glycosyl inositol phosphorylceramide (GIPC) is involved in sensing salt stress [ 195 ], REDUCED HYPEROSMOLALITY INDUCED CALCIUM INCREASE 1 (OSCA1) is an osmotic stress sensor [ 196 ], and CHILLING TOLERANCE DIVERGENCE 1 (COLD1) is a cold stress receptor [ 197 , 198 ].…”

Transcript Profiling Identifies Gene Cohorts Controlled by Each Signal Regulating Trans-Differentiation of Epidermal Cells of Vicia faba Cotyledons to a Transfer Cell Phenotype

“…Across ETC development Ca 2+ exerted greater control over the signaling and cell wall TC functional categories while auxin regulated a slightly higher number of ETC-specific DEGs encoding proteins involved in intracellular organization and nutrient transporter categories ( Table 3 ). In addition to the well described Ca 2+ signaling pathways regulating plant development ( Niu and Liao, 2016 ), a recent study has documented expression of genes encoding cell wall metabolizing enzymes positively regulated by Ca 2+ along with similar impacts on genes encoding nutrient transporters ( Wang et al, 2015 ). Similarly, as reported for other plant systems, auxin regulates expression of genes encoding proteins contributing to intracellular organization and to membrane transport of nutrients (e.g., Dai et al, 2009 ; Omelyanchuk et al, 2017 ).…”

Calcium-permeable cation channels are involved in uranium uptake in Arabidopsis thaliana

“…Additional Ca 2+ -permeable cation channels belonging to the NSCCs, MSCCs, and VDCCs are likely able to take part of U uptake in roots. To support this hypothesis and the postulate of our approach (nutrient depletion inducing the upregulation of ion carriers and, then, an improved U uptake), previous transcriptomic analyses have shown that several genes coding Ca 2+ -permeable channels are upregulated in Arabidopsis plants starved with Ca, of which glutamate-like receptors (GLR1.2,1.4,2.5,2.8), annexins (ANN1,2,4,7), mechanosensitive ion channel proteins (MSL9,10) and cyclic nucleotide-gated ion channels (CNGC 9,11,19) (Table S4) (Wang et al, 2015).…”

“…Data fromWang et al (2015) Arabidopsis transcriptional response to extracellular Ca 2+ depletion involves a transient rise in cytosolic Ca2+ . J Int Plant Biol 57,[138][139][140][141][142][143][144][145][146][147][148][149][150] …”