The Pea SAD Short-Chain Dehydrogenase/Reductase: Quinone Reduction, Tissue Distribution, and Heterologous Expression

• Published in: Plant physiology (Bethesda) Vol. 155; no. 4; pp. 1839 - 1850
• Main Authors: Scherbak, Nikolai, Ala-Häivälä, Anneli, Brosché, Mikael, Böwer, Nathalie, Strid, Hilja, Gittins, John R., Grahn, Elin, Eriksson, Leif A., Strid, Åke
• Format: Journal Article
• Language: English
• Published: United States American Society of Plant Biologists 01-04-2011
• Subjects: Amino Acid Sequence; Antiserum; Arabidopsis - enzymology; Arabidopsis - genetics; Biochemistry; Biokemi; CELL BIOLOGY AND SIGNAL TRANSDUCTION; Chemical Sciences; Chemistry; Dehydrogenases; Enzymes; Epidermal cells; Fatty Acid Synthases - metabolism; Gene Expression Regulation, Plant; Kemi; Leaves; Molecular Sequence Data; NADH, NADPH Oxidoreductases - metabolism; NATURAL SCIENCES; NATURVETENSKAP; Ovule - metabolism; Peas; Pisum sativum - enzymology; Pisum sativum - genetics; Pisum sativum - radiation effects; Plant Epidermis - metabolism; Plant Leaves - metabolism; Plant Proteins - genetics; Plant Proteins - metabolism; Plant Stems - metabolism; Plants; Plants, Genetically Modified - enzymology; Plants, Genetically Modified - genetics; Promoter Regions, Genetic; Quinones; Quinones - metabolism; Seeds; Stems; Substrate Specificity; Ultraviolet Rays
• ISSN: 0032-0889; 1532-2548; 1532-2548
• DOI: 10.1104/pp.111.173336

The pea (Pisum sativum) tetrameric short-chain alcohol dehydrogenase-like protein (SAD) family consists of at least three highly similar members (SAD-A, -B, and -C). According to mRNA data, environmental stimuli induce SAD expression. The aim of this study was to characterize the SAD proteins by examining their catalytic function, distribution in pea, and induction in different tissues. In enzyme activity assays using a range of potential substrates, the SAD-C enzyme was shown to reduce one-or two-ring-membered quinones lacking long hydrophobic hydrocarbon tails. Immunological assays using a specific antiserum against the protein demonstrated that different tissues and cell types contain small amounts of SAD protein that was predominantly located within epidermal or subepidermal cells and around vascular tissue. Particularly high local concentrations were observed in the protoderm of the seed cotyledonary axis. Two bow-shaped rows of cells in the ovary and the placentai surface facing the ovule also exhibited considerable SAD staining. Ultraviolet-B irradiation led to increased staining in epidermal and subepidermal cells of leaves and stems. The different localization patterns of SAD suggest functions both in development and in responses to environmental stimuli. Finally, the pea SAD-C promoter was shown to confer heterologous wound-induced expression in Arabidopsis (Arabidopsis ihaliana), which confirmed that the inducibility of its expression regulated at the transcriptional level.