Transcription factors SlMYB41, SlMYB92 and SlWRKY71 regulate gene expression in tomato exodermis

Root barrier cell types, like the endodermis and exodermis, are crucial for plant acclimation to environmental stresses. Deposition of suberin, a hydrophobic polymer, in these cell layers restricts the movement of molecules and plays a vital role in stress responses. This study investigates the role of SlMYB41, SlMYB92 and SlWRKY71 transcription factors (TFs) in regulating suberin biosynthesis in the tomato ( Solanum lycopersicum ) root exodermis by genetic perturbation. RNA sequencing revealed a significant overlap between differentially expressed genes regulated by these TFs, suggesting a shared regulatory network. Gene set enrichment analyses highlighted their role in lipid and suberin biosynthesis as well as overrepresentation of exodermis-enriched transcripts. Furthermore, transactivation assays demonstrated that these two MYBs promote the expression of suberin-related genes, while SlWRKY71 represses them. These results indicate a complex antagonistic relationship. This study advances our understanding of the regulatory mechanisms controlling exodermis suberization in tomato roots, providing insights into how plants adapt to environmental challenges.