Fuente: PubMed "Tomato process" Plant Cell Rep. 2026 Jul 4;45(7):217. doi: 10.1007/s00299-026-03893-8.ABSTRACTSlBBX17 positively regulates tomato defense by modulating JA-mediated signaling. Jasmonic acid (JA) is a key plant defense metabolite, particularly against herbivory and necrotrophic pathogens. The MYC2 transcription factor (TF), a core TF of the JA response, is repressed by its interaction with JAZ proteins, members of the TIFY/JAZ protein family. Biotic stress stimuli trigger the accumulation of the bioactive JA-Ile conjugate, which binds to the SCFCOI1-JAZ co-receptor complex, promoting the ubiquitination and subsequent degradation of JAZ proteins, thereby releasing MYC2 to activate downstream target genes. JAZ proteins also regulate other signaling pathways through protein-protein interactions with TFs. However, interactions between JAZs and BBX TFs, emerging regulators of several physiological and developmental processes in plants, remain underexplored. In this study, we revisited the SlTIFY/JAZ family in the tomato (Solanum lycopersicum) genome, examining their diversity, domain topology, and conserved motifs. Transcriptional profiling of SlTIFY/JAZs and SlBBXs in tomato leaves revealed three distinct gene groups based on their response to JA, with some being intensely upregulated, displaying SlMYC2-like expression, or downregulated. Further investigation of differentially expressed SlJAZs and SlBBXs in different genotypes of tomato hairy root cultures underscored the dependency of SlCOI1, and, at least partially, of SlMYC1 and/or SlMYC2 for their JA-mediated transcriptional modulation. The expression patterns pinpointed SlBBX17 as a SlMYC2-dependent JA-responsive gene. Transactivation assays further indicate that SlMYC2 upregulates SlBBX17 expression. Functional analyses revealed that SlBBX17 positively contributes to plant defense, because loss-of-function genotypes displayed increased susceptibility to Spodoptera frugiperda herbivory, whereas overexpression enhanced resistance. Together, our results point to SlBBX17 as a JA-responsive regulator that modulates defense responses.PMID:42401757 | PMC:PMC13333002 | DOI:10.1007/s00299-026-03893-8