Polyamine concentrations are dynamically regulated during plant-Pseudomonas syringae interactions

ROSSI FR; VILAS JM; ROMERO FM; RUIZ OA; GÁRRIZ A

Buenos Aires

Congreso; Reunión Conjunta de Sociedades de Biociencias; 2017

Due to their abilities to bind polyanions such as nucleic acids and proteins, the polyamines putrescine, spermidine and spermine are involved in several cellular responses. For instance, these amines participate in the activation of plant defense responses and are required for virulence of plant pathogens. Thus, the modulation of their metabolism plays essential roles in plant-pathogen interactions. In this work, we challenged plants with different pathovars of the bacteria Pseudomonas syringae to evaluate the changes in the concentrations of polyamines occurring in contrasting pathogenic interactions. Our analysis demonstrated that polyamines are increased in tomato in response to a virulent strain, which was associated to the induction of several polyamine metabolic genes from the plant and the bacteria. These results suggest that the metabolism of both organisms modulates polyamine contents in infected tissues. Interestingly, the rise in the concentration of putrescine was particularly higher in apoplastic fluids. A further exploration of the polyamine profiles using Arabidopsis plants demonstrated that non-pathogenic strains inducing the hypersensitive response provoked a remarkable increment in their concentrations, which was not observed by using an avirulent non-host bacteria. Thus, specific regulatory mechanisms may modulate polyamine metabolism in different biological interactions