Transcription factor AtWRKY43 enhances drought tolerance by positively regulating the expression of AtSWEET5

Drought exerts negative effects on plant growth and crop productivity. Sugars play a crucial role in enhancing drought tolerance by acting as osmoprotectants. Sugar transporters AtSWEETs are essential for maintaining sugar distribution equilibrium and facilitating effective adaptation to drought stress. In the study, transcriptomic analysis showed that WRKY transcription factor AtWRKY43 plays a key role in modulating gene expression patterns that enhance the plant's ability to accumulate sugars, which in turn supports osmotic adjustment and overall drought stress resilience. AtWRKY43 was identified as a promoter of sugar accumulation through its induction of transcriptional expression of AtSWEET5, thereby influencing drought tolerance. We observed an upregulation in the expression of the gene AtSWEET5 during drought stress. The mutant atsweet5 exhibited increased sensitivity to drought compared to Col-0, possibly due to increased H₂O₂ content and disrupted sugar homeostasis. Our research highlights the critical roles of AtWRKY43 and AtSWEET5 in modulating drought stress, providing new gene targets for developing crop varieties with enhanced sugar content. Therefore, it is imperative to understand the impact of drought stresses on sugar transport and transporters at both genetic and molecular levels in order to maintain optimal sugar balance in plants experiencing drought stress.