The role of sucrose as a signaling molecule in plants was originally proposed several decades ago. However, recognition of sucrose as a true signal has been largely debated and only recently this role has been fully accepted. The best-studied cases of sucrose signaling involve metabolic processes, such as the induction of fructan or anthocyanin synthesis, but a large volume of scattered information suggests that sucrose signals may control a vast array of developmental processes along the whole life cycle of the plant.
View Article and Find Full Text PDFProtein phosphatase type 2A (PP2A) activity is required for the sucrose induction of fructan metabolism in wheat leaves, as shown in experiments with the addition of the specific inhibitor okadaic acid (OA) together with sucrose. However, a decrease in total PP2A activity has been found along sucrose treatment. Here we analyze the effect of sucrose feeding to wheat leaves on PP2A activity profiles after Deae-Sephacel and Superose separation, in comparison with those of control leaves.
View Article and Find Full Text PDFIn this work, we analyze protein phosphatase (PP) involvement in the sucrose-mediated induction of fructan metabolism in wheat (Triticum aestivum). The addition of okadaic acid (OA), a PP-inhibitor, to sucrose-fed leaves reduced fructosylsucrose-synthesizing activity (FSS) induction in a dose-dependent manner. The expression of the two enzymes that contribute to FSS activity, 1-SST (1-sucrose:sucrose fructosyltransferase, E.
View Article and Find Full Text PDFFructans are fructose polymers synthesized from sucrose in the plant vacuole. They represent short- and long-term carbohydrate reserves and have been associated with abiotic stress tolerance in graminean species. We report the isolation and characterization of a putative sucrose:fructan 6-fructosyltransferase (6-SFT) gene from a Patagonian grass species, Bromus pictus, tolerant to drought and cold temperatures.
View Article and Find Full Text PDFThe presence of sucrose (Suc) in plastids was questioned for several decades. Although it was reported some decades ago, neither Suc transporters nor Suc metabolizing enzymes were demonstrated to be active in those organelles. By biochemical, immunological, molecular and genetic approaches we show that alkaline/neutral invertases (A/N-Invs) are also localized in chloroplasts of spinach and Arabidopsis.
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