Proteomic analysis of defense response of wildtype Arabidopsis thaliana and plants with impaired NO-homeostasis


To investigate the importance of SNO in plant defense response we performed a proteomic analysis of Arabidopsis wildtype and GSNO-reductase knock-out plants infected with both the avirulent and virulent pathogen strains of Pseudomonas syringae. Interestinly, atgsnor and wildtype plants display overlapping, but also significantly different defense responses after infection with virulent and avirulent Pseudomonas syringae. Plants have different defense strategies and changes in one pathway might not per se have a significant effect on the whole defense response. Thus, knock-out plants just might switch their strategy to another defense pathway/mechanism and try to compensate the lost function. Probably this is the way how atgsnor plants react, because we observed clear differences at the proteome level between wildtype and AtGSNOR knock-out plants during defense response. The molecular mechanisms of how GSNOR regulate processes in plants are still unclear and need to be analysed in the future.

Christian Lindermayr

Representative illustration of soluble protein fraction from Arabidopsis leaf extracts. Time-dependent changes of protein accumulation in gel region exhibiting intense protein regulation due to infection with avirulent pathogen. Red circles: >2-fold accumulation; green circles: <2-fold accumulation.