Bioinformatics Analysis and Expression Profiling of the Jasmonic Acid-responsive Transcription Factor SlMYB83

Abstract

Background: Tomato (Solanum lycopersicum) stress responses are strongly regulated by jasmonic acid signaling—especially via MYB transcription factors—yet key regulators like SlMYB83 in JA-deficient spr2 mutants remain largely uncharacterized. Aims: Based on the tomato SlMYB83 gene previously identified through transcriptome screening, this study aims to elucidate its protein structural characteristics, tissue‑specific expression patterns, and responsive relationship to jasmonic acid (JA) signaling, thereby providing a foundation for subsequent functional studies. Study Design: A research design integrating bioinformatics prediction with gene expression analysis was adopted to systematically characterize the protein properties of SlMYB83 and its expression changes in a mutant and under exogenous hormone treatment. Methods: Bioinformatics analyses were performed using tools such as ProtParam, SignalP-5.0, TMHMM, SOPMA, SWISS-MODEL, Plant-mPLoc, PLANTCARE, and STRING. Quantitative real‑time PCR (qRT‑PCR) was used to examine tissue‑specific expression as well as expression differences in the spr2 mutant and under MeJA treatment. Results: SlMYB83 was characterized as a hydrophilic protein lacking signal peptide and transmembrane domains, localized to the nucleus, and containing a SANT domain. Its promoter harbored stress‑responsive elements including MeJA and ABA. The gene exhibited the highest expression in leaves and the lowest in fruits. SlMYB83 expression was significantly upregulated in the spr2 mutant but markedly downregulated following exogenous MeJA treatment. Conclusions: This study elucidated the fundamental characteristics of the SlMYB83 protein and revealed that JA negatively regulates its expression, thereby laying a foundation for subsequent functional research.