Differential gene regulation in potato cells and plants upon abrupt or gradual exposure to water stress

Abstract

Potato cDNA microarray slides (TIGR 1 K) were used to compare changes in gene expression of two potato cell populations subjected to shock or gradual exposure to PEG-mediated water stress. A total of 180 transcripts were found to be statistically up- or down-regulated in PEG-shocked or gradually stressed cells, compared to untreated control cells. Up-regulated genes in shocked cells were prevalently involved in carbohydrate metabolism, cellular communication, and signal transduction. In cells stressed gradually, the most represented induced genes were those involved in signal transduction, in response to environmental signals and in the regulation of transcription and translation machineries, including the heat shock protein 90-2, ribosomal and RNA-binding proteins. The expression of selected up-regulated genes was also tested in potato plants subjected to slow soil-drying conditions. Interestingly, the rgga gene, encoding an RNA-binding protein, was strongly induced in both leaves and roots of water-stressed potato plants, supporting its putative function in adaptive mechanisms to water stress. Pointing to differences in gene expression between shock-like and adaptive response, our findings might contribute to the controversial debate on the biological function of stress-responsive genes in cell damage repair or in restoring homeostasis and elaborating longer term responses for adaptation

The Arabidopsis RNA-Binding Protein AtRGGA Regulates Tolerance to Salt and Drought Stress

“…In a previous report, we identified StRGGA, a potato gene encoding a putative RBP whose expression was specifically induced in cultured cells adapted to high concentrations of PEG (Ambrosone et al, 2011; Fig. 1).…”

“…FM209282), whose gene expression is specifically induced in culture cells of potato gradually adapted to high concentrations of PEG. Exposure of potato cells to abrupt osmotic stress did not elicit a change in StRGGA transcript abundance (Ambrosone et al, 2011;Fig. 1A;Supplemental Table S1).…”

“…Potato (Solanum tuberosum 'Desirèe') cell cultures were generated, maintained, and gradually or abruptly exposed to 20% (w/v) PEG 8000 as described previously (Leone et al, 1994;Ambrosone et al, 2011). Arabidopsis (Arabidopsis thaliana) MM2D cells (ecotype Landsberg erecta) were maintained as described (Menges and Murray, 2002) in continuous dark conditions.…”

“…In an effort to identify genes important for adaptation to osmotic stress, we isolated StRGGA, a gene encoding a putative RBP, whose expression was induced in potato (Solanum tuberosum) cell cultures gradually adapted to high concentrations of polyethylene glycol (PEG), while no change in StRGGA expression was observed when cells were shocked with PEG (Ambrosone et al, 2011). Here, we present the characterization of the putative RGGA ortholog in Arabidopsis.…”

Seedling response to water stress in valley oak (Quercus lobata) is shaped by different gene networks across populations

“…Similar to this study, ribosomal genes were upregulated under soil drying in some accessions of Arabidopsis thaliana (Des Marais et al, ). Ribosomal proteins were also upregulated in gradually water‐stressed potato cells but downregulated under a shock treatment, possibly indicating that maintaining protein synthesis is important for stress acclimation, but simply shuts down in more stressful conditions (Ambrosone et al, ).…”