Towards functional characterzation of Proline Dehydrogenase isoforms in plant defence

RIZZI YS; CECCHINI NM; ALVAREZ ME

Mendoza

Congreso; XLVIII Reunión SAIB; 2012

SAIB

Towards functional characterization of the Proline Dehydrogenase isoforms in the plant defence Rizzi YS, Cecchini NM, Alvarez ME CIQUIBIC-CONICET, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba ProDH is the first of two enzymes involved in the oxidation of proline into glutamic acid. In plants, the enzyme is required for normal development of the Hypersensitive Response, a defense against biotrophic pathogens. The Arabidopsis ProDH isoforms, ProDH1 and ProDH2, differ in some physiological functions. ProDH1 and ProDH2 genes contain cis elements mediating responses to salcylic acid (SA) and jasmonic acid (JA). However, their differential sensitivity to infections inducing these pathways remains unknown. To start evaluating this point we treated plants with pathogens or hormones. In wild type plants the infection with Pseudomonas syringae Avr-Rpm1 induced both genes, whereas SA and JA generated differential effects on their expression. In contrast, in sid2 and jar1 mutants impaired in the SA or JA pathways, this pathogen stimulated abnormal responses for ProDH1 and ProDH2 with differences among both kind of mutants. Besides, Prodh2 was induced by the necrotrophic pathogen Botrytis cinerea. These results suggest that both ProDH isoforms may contribute to pathogen resistance under different infection conditions, probably by displaying non-redundant functions in plant immunity.