Genome-wide Identification of Growth‑regulating Factor (GRF) and GRF‑interacting Factor (GIF) Gene Families across Three Solanaceae Species with Functional Analysis in Pepper Regeneration

Yanping Wang^1,2,3Li Jia^1,2,3Han Wang^1,2,3Xiujuan Zhou^1,2,3Congsheng Yan^1,2,3Qiangqiang Ding^1,2,3Xiujing Hong^1,2,3Yanxiang Dong^1,2,3Yan Wang^1,2,3*HaiKun Jiang^1,2,3*

• ¹Institute of Vegetables, Anhui Academy of Agricultural Sciences, Hefei, China
• ²Key Laboratory of Horticultural Crop Germplasm innovation and Utilization (Co-construction by Ministry and Province), Institute of Horticulture, Anhui Academy of Agricultural Sciences, Hefei, China
• ³Anhui Provincial Key Laboratory for Germplasm Resources Creation and High-Efficiency Cultivation of Horticultural Crops, Institute of Vegetables, Anhui Academy of Agricultural Sciences, Hefei, China

The growth-regulating factor (GRF) and GRF-interacting factor (GIF) gene families play crucial roles in enhancing plant genetic transformation efficiency. However, the functional contributions of pepper GRF and GIF genes in improving transformation efficiency remain unexplored. In this study, we identified 31 GRF genes and 9 GIF genes across pepper, tomato, and tobacco. A systematic analysis was conducted to characterize their phylogenetic relationships, gene structures, collinearity, and expression patterns. Collinearity analysis revealed large-scale duplication events among these three Solanaceae species. Furthermore, qRT-PCR analysis demonstrated significantly elevated expression levels of pepper GRF and GIF genes in regenerative tissues, indicating their critical functional roles during pepper regeneration processes. Our findings provide novel insights into the evolution of GRF and GIF gene families in Solanaceous plants and identify several key candidate genes for future functional studies aimed at enhancing pepper regeneration efficiency and genetic transformation.