Metabolite profiling and network analysis reveal coordinated changes in grapevine water stress response

Abstract

BackgroundGrapevine metabolism in response to water deficit was studied in two cultivars, Shiraz and Cabernet Sauvignon, which were shown to have different hydraulic behaviors (Hochberg et al. Physiol. Plant. 147:443–453, 2012).ResultsProgressive water deficit was found to effect changes in leaf water potentials accompanied by metabolic changes. In both cultivars, but more intensively in Shiraz than Cabernet Sauvignon, water deficit caused a shift to higher osmolality and lower C/N ratios, the latter of which was also reflected in marked increases in amino acids, e.g., Pro, Val, Leu, Thr and Trp, reductions of most organic acids, and changes in the phenylpropanoid pathway. PCA analysis showed that changes in primary metabolism were mostly associated with water stress, while diversification of specialized metabolism was mostly linked to the cultivars. In the phloem sap, drought was characterized by higher ABA concentration and major changes in benzoate levels coinciding with lower stomatal conductance and suberinization of vascular bundles. Enhanced suberin biosynthesis in Shiraz was reflected by the higher abundance of sap hydroxybenzoate derivatives. Correlation-based network analysis revealed that compared to Cabernet Sauvignon, Shiraz had considerably larger and highly coordinated stress-related changes, reflected in its increased metabolic network connectivity under stress. Network analysis also highlighted the structural role of major stress related metabolites, e.g., Pro, quercetin and ascorbate, which drastically altered their connectedness in the Shiraz network under water deficit.ConclusionsTaken together, the results showed that Vitis vinifera cultivars possess a common metabolic response to water deficit. Central metabolism, and specifically N metabolism, plays a significant role in stress response in vine. At the cultivar level, Cabernet Sauvignon was characterized by milder metabolic perturbations, likely due to a tighter regulation of stomata upon stress induction. Network analysis was successfully implemented to characterize plant stress molecular response and to identify metabolites with a significant structural and biological role in vine stress response.

Cultivar specific metabolic changes in grapevines berry skins in relation to deficit irrigation and hydraulic behavior

“…Similarly, withholding water from the two cultivars resulted in a larger alteration of the maximal quantum yield efficiency and leaf metabolism in Shiraz (Hochberg et al, 2013a(Hochberg et al, , 2013b. Combining these evidences with current results of berry metabolism suggest a systemic larger effect of the water stress on Shiraz vines as compared with CS.…”

“…Additionally, hydraulic conductance and embolism in respect to xylem architecture could present a significant contribution to the phenomena . In a recently published study (Hochberg et al, 2013a(Hochberg et al, , 2013b, Shiraz and Cabernet Sauvignon (CS) presented significantly different hydraulic behavior and metabolic responses in the leaf. Under similar irrigation treatments in both cultivars, tighter stomata regulation of CS resulted in improved water balance and milder metabolic perturbation.…”

LC-HRMS Based Non-Targeted Metabolomic Profiling of Wheat (<I>Triticum aestivum</I> L.) under Post-Anthesis Drought Stress

“…Metabolic composition is highly variable in a wide variety of plants including major crops like wheat [16], rice [17], maize [15], and cassava [14]. These metabolic changes in plants have also occurred due to progressive water deficit conditions accompanied by lower leaf water potentials [18]. Water stress induces metabolic changes and accumulation of metabolites including proline, ascorbic acid, glutathione, phenolics, and detoxifying enzymes in cereals [19] [20].…”

Identification and characterization of a seed-specific grapevine dehydrin involved in abiotic stress response within tolerant varieties

“…late-embryogenesis-abundant (LEA) proteins (Cramer et al, 2013;Hochberg et al, 2013). Indeed, higher expression levels of dehydrin in tolerant genotypes under drought stress are commonly observed (Hu et al, 2010); nevertheless, this is not always the case, as differences in expression levels between tolerant and sensitive genotypes are often dependent on the type of dehydrin as well as the duration of the stress (Yang et al, 2012).…”