INVESTIGADORES
ROSSI franco Ruben
congresos y reuniones científicas
Título:
Modulation of Putrescine Metabolism in Arabidopsis thaliana by Salicylic Acid
Autor/es:
ROSSI FRANCO R; MARÍA MARINA; PIECKENSTAIN FERNANDO L
Lugar:
Rosario
Reunión:
Congreso; 50 Reunion anual de la sociedad argentina de investigaciones en bioquimica y biologia molecular; 2014
Resumen:
Salicylic
acid (SA) is a key hormone for defense responses in plants, and plays a
critical role in resistance to pathogens. Increments of SA levels activate
different signaling cascades in which H2O2 acts as a
secondary messenger and in turn activates a large number of mechanisms that
contribute to overall plant defense. Polyamines are a group of compounds with
multiple physiological roles, which also participate in defense mechanisms
against pathogens. The metabolism of the diamine putrescine (Put) is altered by
stressful conditions in plants, which generally result in increased Put levels.
Previous results showed that exogenous addition of SA induces a high increase
in Put levels. In this work, we give evidence that this increase in Put level
is mediated by an increase in arginine decarboxylase 2 (ADC2) activity.
Moreover, apoplastic Put levels were increased and amine oxidase activity was
decreased in plants treated with exogenous SA. Diaminebenzidine (DAB) staining
of adc2 mutants (with contain lower Put levels than WT plants), showed that
these plants accumulate higher H2O2 levels than WT plants
after SA addition. Put supplementation to adc2 mutant plants decreased the H2O2
levels. These results indicate that the accumulation of Put, after the
exogenous addition of SA, probably contributes to regulate H2O2
levels during plant defense responses.