Biochemical characterization of proline dehydrogenase in Arabidopsis mitochondria. (14th May 2014)

• Record Type: Journal Article
• Authors: Schertl, Peter; Cabassa, Cécile; Saadallah, Kaouthar; Bordenave, Marianne; Savouré, Arnould; Braun, Hans‐Peter
• Is Part Of: FEBS journal. Volume 281:Number 12(2014)
• Page Start: 2794
• Page End: 2804
• Publication Date: 2014-05-14
• Subjects: Biochemistry -- Periodicals; Molecular biology -- Periodicals; Pathology, Molecular -- Periodicals; 572
• DOI: 10.1111/febs.12821
• Languages: English
• ISSNs: 1742-464X

Abstract

<abstract abstract-type="main" id="febs12821-abs-0001"> <title> <x xml:space="preserve">Abstract</x> </title> <p>Proline has multiple functions in plants. Besides being a building block for protein biosynthesis proline plays a central role in the plant stress response and in further cellular processes. Here, we report an analysis on the integration of proline dehydrogenase (ProDH) into mitochondrial metabolism in <italic>Arabidopsis thaliana</italic>. An experimental system to induce ProDH activity was established using cell cultures. Induction of ProDH was measured by novel photometric activity assays and by a ProDH <italic>in gel</italic> activity assay. Effects of increased ProDH activity on other mitochondrial enzymes were systematically investigated. Activities of the protein complexes of the respiratory chain were not significantly altered. In contrast, some mitochondrial dehydrogenases had markedly changed activities. Activity of glutamate dehydrogenase substantially increased, indicating upregulation of the entire proline catabolic pathway, which was confirmed by co‐expression analyses of the corresponding genes. Furthermore, activity of <sc>d</sc>‐lactate dehydrogenase was increased. <sc>d</sc>‐lactate was identified to be a competitive inhibitor of ProDH in plants. We suggest that induction of <sc>d</sc>‐lactate dehydrogenase activity allows rapid upregulation of ProDH activity during the short‐term stress response in plants.</p> </abstract>