DEVELOPMENTAL FEATURES AND STRESS-INDUCED RESPONSES IN KNOCKDOWN L-PROLINE DEHYDROGENASE PLANTS

CECCHINI NM; MONTEOLIVA MI; ÁLVAREZ ME

Congreso; - SAIB - th 44 Annual Meeting Argentine Society for Biochemistry and Molecular Biology Research XLIV Reunión Anual Sociedad Argentina de Investigación en Bioquímica y Biología Molecular; 2008

We have recently found that tissues triggering the HypersensitiveResponse (HR) upon recognition of avirulent pathogen displayearly transcriptional of proline (Pro) degradation genes. Activationof ProDH (Pro dehydrogenase) and reduction of P5CDH (P5Cdehydrogenase) are detected at the center, but not the periphery, ofthe HR lesion. Such responses are induced in wild type plantstreated with exogenous salicylic acid (SA). Consistently, sid2 andnpr1 mutant plants defective in the SA pathway, do not activatethese changes in response to avirulent pathogen. Interestingly,ProDH knockdown plants (siRNAProDH) show reduced cell deathduring incompatible interactions suggesting the involvement ofProDH in HR generation. Putative contributions of this enzyme toHR factors are analyzed. We also evaluate developmental featuresof the siRNAProDH lines.