A Plasma Membrane Intrinsic Protein Gene Involved in Promoting Petal Expansion and Drought Resistance in .

, a native to China, is renowned as a highly popular gardening plant. However, this plant faces significant challenges from drought stress, which can adversely affect its flowering. In this study, we found that the plasma membrane-localized gene exhibited a substantial upregulation during the flowering stages and in response to drought stress. GUS staining has illustrated that the promoter can drive GUS activity under drought conditions. The overexpression of was found to enhance petal size by modulating epidermal cell dimensions in and tobacco. Moreover, this overexpression also bolstered drought tolerance, as evidenced by a reduction in stomatal aperture in both species. Furthermore, yeast one-hybrid (Y1H) and dual-luciferase (Dual-LUC) assays have indicated that the transcription factor OfMYB28 directly binds to the promoter, thereby regulating its expression. Together, we speculated that a module of OfMYB28- was not only involved in the enhancement of petal size but also conferred the improvement of drought tolerance in . These results contribute valuable insights into the molecular function of the gene and lay a foundation for molecular breeding strategies in .