Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)A major goal in post-genomic biology is the description of physiological functions ill terms of gene pathway behavior. In this work, we present the first investigation of expression alterations in ninety-three pathways representing physiological functions of the plant A. thaliana induced by a A parasitica elicitor (NLPpp) using microarray data publicly available at the AtGenExpress database. Using a novel statistical analysis developed to detect pathway alterations, we identified the gene pathways, hereby called groups of functionally associated genes (defined according to the TA1R/Gene Ontology and other databases), that are significantly altered in response to the elicitor. Instead of looking at individual gene responses, Our analysis allowed a detailed characterization of the time ordering of pathways alterations in response to the NLPpp, their physiological implications and specificity. We also observed the activation of genes associated with vesicle trafficking and ROS production implying the initiation of the senescence of the wounded plant tissue. (C) 2009 Elsevier B.V. All rights reserved.3882045154522Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)CNPq [506414/2004-3, 151171/2007-6]