This study investigates the differential gene expression in response to mechanical wounding and insect feeding in Arabidopsis using cDNA microarrays. The authors analyzed the timing, dynamics, and regulation of 150 genes in mechanically wounded leaves, finding that the temporal accumulation of transcripts correlated with the appearance of jasmonate family oxylipins. They identified a large number of COI1-dependent and COI1-independent wound-inducible genes, with water stress contributing significantly to their regulation. When comparing mechanical wounding with insect feeding by the cabbage butterfly (Pieris rapae), they observed distinct transcript profiles. One gene, encoding a hevein-like protein (HEL), was specifically induced by insect feeding but not by wounding. The results highlight differences in plant responses to mechanical wounding and insect damage, providing insights into the feeding strategies of P. rapae to minimize the activation of certain defense-related genes.This study investigates the differential gene expression in response to mechanical wounding and insect feeding in Arabidopsis using cDNA microarrays. The authors analyzed the timing, dynamics, and regulation of 150 genes in mechanically wounded leaves, finding that the temporal accumulation of transcripts correlated with the appearance of jasmonate family oxylipins. They identified a large number of COI1-dependent and COI1-independent wound-inducible genes, with water stress contributing significantly to their regulation. When comparing mechanical wounding with insect feeding by the cabbage butterfly (Pieris rapae), they observed distinct transcript profiles. One gene, encoding a hevein-like protein (HEL), was specifically induced by insect feeding but not by wounding. The results highlight differences in plant responses to mechanical wounding and insect damage, providing insights into the feeding strategies of P. rapae to minimize the activation of certain defense-related genes.