Identification of the <i>GST</i> Gene Family and Functional Analysis of <i>RcGSTF2</i> Related to Anthocyanin in <i>Rosa chinensis</i> ‘Old Blush’

The rose (<i>Rosa chinensis</i>), with its rich color variations and elegant form, holds a significant position in the global floriculture industry, where the color of its petals and the content of anthocyanins are crucial for enhancing the plant’s ornamental value and market competitiveness. Nevertheless, the precise roles of the GST gene family in roses, especially regarding their participation in anthocyanin transport and the modulation of petal color, remain poorly elucidated. In the present investigation, we identified 83 rose glutathione S-transferase (GST) genes through whole-genome analysis. The identification and functional analysis of <i>RcGSTF2</i> were conducted exclusively in the ‘Old Blush’ cultivar of <i>Rosa chinensis</i>. We employed bioinformatics, tissue expression analysis, subcellular localization, and transient expression validation to explore the function of the <i>RcGSTF2</i> gene in anthocyanin transport and accumulation. We found that <i>RcGSTF2</i> is closely related to anthocyanin-associated GSTs and demonstrated a conserved domain with high sequence similarity. Molecular docking analysis revealed potential binding modes between RcGSTF2 and cyanidin-3,5-diglucoside, suggesting a role in anthocyanin transport. Subcellular localization indicated that <i>RcGSTF2</i> is associated with the cell membrane. Overexpression of <i>RcGSTF2</i> in rose plants significantly increased anthocyanin accumulation, while silencing <i>RcGSTF2</i> reduced anthocyanin content, highlighting its crucial role in regulating anthocyanin accumulation. This research investigates the functions of the GST gene family in roses, laying the groundwork for developing more colorful and resilient rose cultivars, with the functional analysis of <i>RcGSTF2</i> being a key contribution to the floriculture industry’s genetic enhancement efforts.