Abstract
The genus Selaginella holds a key phylogenetic position as a sister species to vascular plants, encompassing desiccation-tolerant members. Some Selaginella species thrive in extremely arid conditions, enduring significant water loss and recovering upon rehydration. Consequently, Selaginella has emerged as a model system for studying desiccation tolerance in plant science. However, the absence of an efficient genetic transformation system has limited the utility of Selaginella species as a model. To address this constraint, we developed a nanoparticle-mediated transformation tool utilizing arginine-functionalized nanohydroxyapatites. This biocompatible system enabled the transient expression of the GFP, GUS, and eYGFPuv reporter genes in Selaginella moellendorffii. Establishing a stable genetic transformation technique for S. moellendorffii holds promise for application to other Selaginella species. This tool could be instrumental in identifying genetic resources for crop improvement and understanding genome-level regulatory mechanisms governing desiccation tolerance in Selaginella species. Furthermore, this tool might aid in identifying key regulatory genes associated with desiccation tolerance, offering potential applications in enhancing drought-sensitive crops and ensuring sustainable food production.