A red beet (Beta vulgaris) UDP-glucosyltransferase gene induced by wounding, bacterial infiltration and oxidative stress

Abstract

Mechanical wounding, infiltration with P. syringae or A. tumefaciens, and exposure to an H(2)O(2)-generating system (Glc/Glc oxidase) induce betacyanin synthesis in red beet (Beta vulgaris) leaves. These conditions also induced the expression of BvGT, a gene encoding a glucosyltransferase (GT) from Beta vulgaris. BvGT has a high similarity to Dorotheanthus bellidiformis betanidin-5 GT involved in betacyanin synthesis. Furthermore, the transient expression of a BvGT antisense construct resulted in the reduction of BvGT transcript accumulation and betanin synthesis, suggesting a role for this gene product in betacyanin glucosylation. In addition, the NADPH oxidase inhibitor, diphenylene iodonium (DPI), inhibited the accumulation of the BvGT transcript in response to infiltration with Agrobacterium tumefaciens. Hence, this result suggests that ROS produced by a plasma membrane NADPH oxidase may act as a signal to induce BvGT expression, necessary for betanin synthesis after wounding and bacterial infiltration.

Involvement of betacyanin in chilling-induced photoinhibition in leaves of Suaeda salsa

“…Although some evidences suggest that betacyanins are able to provide protection against photoinhibition induced by high "white" and UV-A irradiances (Vogt et al 1999), little attention has been paid to their involvement in the defence against photo-damage caused by low temperature. The antioxidant properties of betacyanins have also been reported in some systems (Butera et al 2002, Cai et al 2003, Sepúlveda-Jiménez et al 2004, 2005. The production of betacyanins in S. salsa in response to H 2 O 2 treatments suggests that the pigment may function as a ROS scavenger, limiting the oxidative stress caused by environmental stressors (Wang et al 2006a).…”

Plant betalains: Chemistry and biochemistry

“…For formation of betanin, it is not clear which route is favoured, either reaction 8 or 18, or both. However, detection of cD5G and BvGT associated with betanin accumulation through betanidin glucosylation (Sepúlveda-Jiménez et al, 2005;Isayenkova et al, 2006) in red beet, and cloning of cD5GT and B5GT in Amaranthus hypochondriacus indicate the possibility of co-occurrence of both reactions 8 and 18 in biosynthesis pathway of betalains. In amaranthin-accumulating plants (Sasaki et al, 2005a,b), cD5G acts as substrate for glucuronyltransferase leading to formation of amaranthin (reactions 19-20, Fig.…”

Gene expression profiling in soybean under aluminum stress: genes differentially expressed between Al-tolerant and Al-sensitive genotypes

“…Genes encoding UDP-glycosyl transferases Gma.6457 and Gma.30046 at 12 h (Additional file 1), Gma.6457 and Gma.2213 at 48 h (Additional file 2), and Gma.30046 and Gma.2213 at 72 h 290 (Additional file 3) were expressed at high level in PI 416937. UDP-glycolsyl transferases that glucoyslate plant secondary metabolites and hormones have been shown to be triggered by wounding, pathogen infection, and oxidative stress [43]. The glycosylation reaction converts secondary metabolites and hormones to inactive form for storage in vacuole or plastids that become available as needed.…”

“…The glycosylation reaction converts secondary metabolites and hormones to inactive form for storage in vacuole or plastids that become available as needed. Glycosylation of low molecular weight molecules like harmful metabolites or environmental compounds also allow the solubilization of these compounds in water for detoxification and modulation of their biological activity [43]. Biosynthesis and homeostasis of secondary metabolites with antioxidant and detoxification property such polyphenols, benzoic acid and terpeniods could relate these enzymes to Al tolerance.…”