Context of action of Proline Dehydrogenase (ProDH) in the Hypersensitive Response of Arabidopsis

MONTEOLIVA M; RIZZI YS; CECCHINI N; HAJIREZAEI M-R; ALVAREZ ME

BIOMED CENTRAL LTD

Lugar: Londres; Año: 2014 vol. 14 p. 1 - 1

bstract Background: Proline (Pro) dehydrogenase (ProDH) potentiates the oxidative burst and cell death of the plant Hypersensitive Response (HR) by mechanisms not yet elucidated. ProDH converts Pro into Δ1 pyrroline-5-carboxylate (P5C) and can act together with P5C dehydrogenase (P5CDH) to produce Glu, or with P5C reductase (P5CR) to regenerate Pro and thus stimulate the Pro/P5C cycle. To better understand the effects of ProDH in HR, we studied the enzyme at three stages of the defense response differing in their ROS and cell death levels. In addition, we tested if ProDH requires P5CDH to potentiate HR. Results: Control and infected leaves of wild type and p5cdh plants were used to monitor ProDH activity, in vivo Pro catabolism, amino acid content, and gene expression. Wild type plants activated ProDH at all HR stages. They did not consume Pro during maximal ROS accumulation, and maintained almost basal P5C levels at all conditions. p5cdh mutants activated ProDH as wild