Efficient Mesophyll-Derived Protoplast Manipulation System As a Versatile Tool for Characterization of Genes Responding to Multiple Stimuli in Mulberry

Mulberry serves as a crucial element of the global sericulture industry. Functional gene analysis considering resistant traits improvement of mulberry is greatly hindered by its long life cycle and recalcitrance to genetic transformation. A versatile protoplast manipulation system enables rapid and effective transformation for gene functional studies, especially on physiological perceptions and responses to hormones, metabolites, and environmental stimuli is urgently demanded. In this study, we optimized the protocol for isolating mesophyll-derived protoplast from sterile cultures of Morus alba cv. GY62. With sufficient viable protoplasts, polyethylene glycol (PEG)-mediated transient gene expression was developed and a transformation efficiency of nearly 50