systemin and ubenimex

Bestatin, an inhibitor of some aminopeptidases in plants and animals, is a powerful inducer of defense genes in tomato leaves; these genes are also induced by herbivore attacks, mechanical wounding, systemin, and methyl jasmonate. Unlike wounding and systemin, bestatin does not cause an increase in intracellular jasmonic acid concentrations, and inhibitors of the octadecanoid pathway do not inhibit induction by bestatin. Furthermore, defense genes were induced by bestatin in a mutant tomato line (JL-5) with a defect in the octadecanoid pathway. Bestatin therefore appears to be exerting its effects close to the level of transcriptional control of these genes, where it may be inhibiting a regulatory protease.

Topics: Aminopeptidases; Animals; Base Sequence; Gene Expression; Genes, Plant; Leucine; Molecular Sequence Data; Mutation; Oligonucleotide Probes; Peptide Biosynthesis; Peptides; Plant Leaves; Plant Proteins; Protease Inhibitors; Solanum lycopersicum; Transcription, Genetic; Wounds and Injuries