The study found pronounced changes in the expression of stress-responsive transcriptional regulators, including DREB19 and DREB2C, which participate in stress-responsive signalling pathways. The transcriptional changes were consistent with a shift from growth-associated to stress-responsive functions: photosynthesis-related genes were repressed, while pathways associated with oxidative stress responses were activated. The authors describe these patterns as evidence that specific cellular functional categories were altered by the treatment.

The transcriptomic findings were accompanied by measurable changes in cellular redox status. Riboflavin-treated seedlings showed reduced accumulation of reactive oxygen species and lower levels of malondialdehyde, an indicator of diminished lipid peroxidation. The activities of the antioxidant enzymes catalase, superoxide dismutase and ascorbate peroxidase were regulated over time following treatment.

Exogenous riboflavin also altered the expression of genes involved in flavin metabolism, including FMN/FHY, which encodes a key bifunctional enzyme catalyzing the interconversion of riboflavin and FMN in the cytosol. Riboflavin is the precursor of the flavin coenzymes FMN and FAD, which support photosynthesis, mitochondrial electron transport and fatty acid oxidation, and the authors note that the molecular responses underlying the previously reported protective effects of riboflavin application had remained largely unknown.

Collectively, the results indicate that an acute increase in riboflavin availability triggers coordinated transcriptional and redox responses associated with stress-related pathways and flavin metabolism, highlighting the importance of tightly regulated riboflavin homeostasis in plants. The findings are based on seedling-stage Arabidopsis and characterise molecular and biochemical responses to treatment rather than demonstrating crop-level protection.

Subject of Research: Transcriptomic and redox responses of Arabidopsis seedlings to exogenous riboflavin treatment

Article Title: Exogenous riboflavin activates stress-responsive gene networks in Arabidopsis

Article References: Tsitsekian, D., Kamargiakis, E., Mylona, P., Livanos, P., Avgeri, F., Bailes, C. L., Roje, S., Rigas, S., & Daras, G. (2026). Exogenous riboflavin activates stress-responsive gene networks in Arabidopsis. Plant Molecular Biology, 116(6), Article 106. https://doi.org/10.1007/s11103-026-01774-y

Image Credits: AI Generated

DOI: 10.1007/s11103-026-01774-y

Keywords: riboflavin, Arabidopsis, transcriptomics, stress-responsive genes, DREB19, DREB2C, redox homeostasis, reactive oxygen species, flavin metabolism, FMN/FHY, antioxidant enzymes, lipid peroxidation