Transcriptional profiling in Arabidopsis thaliana SLIM1 mutant exposed to boron toxicity

The effects of B (B) toxicity on plants have been investigated for a long time, but the interaction between sulfur metabolism and B has not been sufficiently clarified in this process. Sulfur metabolism plays an important role, especially in the production of compounds such as cysteine, methionine and glutathione (GSH), and is considered a critical component in the stress response of plants. In this study, the effects of sulfur metabolism in response to B toxicity and the role of the SLIM1 transcription factor in this process were investigated. SLIM1 is an important transcription factor that controls the synthesis of sulfur-containing amino acids by regulating sulfur uptake and metabolism. The deficiency of this factor in slim1 mutants leads to disruptions in the functioning of sulfur metabolism. In this study, the effects of sulfur metabolism were investigated in slim1 mutant Arabidopsis thaliana plants exposed to B toxicity.To better understand the functions of sulfur (S) uptake and metabolism in plants at the molecular level, it is necessary to investigate these processes under the effects of B toxicity. For this purpose, in this study, wild-type and slim1 mutant plants of Arabidopsis thaliana exposed to 1 mM and 2 mM B and RNA-Seq analysis were performed. As a result of the analyses, significant changes were observed in genes related to sulfur metabolism and transport in the slim1 control group. While a significant increase in ribosome biogenesis, RNA processing and binding activities was detected in slim1 mutants under B toxicity, glucosinolate biosynthesis processes were suppressed in all slim1 mutants. In addition, it was revealed that ribosome biogenesis and RNA processing processes, together with antioxidant mechanisms, play critical roles in the regulation of defense responses against B toxicity.This study provides important contributions to the understanding of the mechanisms of resistance to B toxicity and reveals that targeting SLIM1 and related mechanisms provides valuable clues for the development of plant varieties resistant to B stress conditions.