Establishment of A PEG-mediated Protoplast Transformation System Based on DNA and CRISPR/Cas9 Ribonucleoprotein Complexes For Banana

Abstract

Background: To date, CRISPR/Cas9 RNPs editing tools have not been applied to genetic modification of banana. Here, the establishment of PEG-mediated banana protoplast transformation system makes it possible to build an efficient DNA- free method for the site-directed mutagenesis system.Results: Protoplasts are a versatile platform for transient expression in plant science. In this study, we established a PEG-mediated banana protoplast transformation system. This system was further optimized for successfully delivering plasmids of CRISPR/Cas9 and CRISPR/Cas12a , CRISPR/Cas9 ribonucleoproteins (RNPs) that targeted PDS gene into banana protoplasts. Specific bands were observed in PCR-Restriction Enzyme Digestion (PCR-RE) assays and monoclonal sequencing further confirmed the occurring of indels at target sites. Deep amplicon sequencing results showed that the editing efficiency of CRISPR/Cas9 system was higher than that of the other two systems. Conclusions: The PEG-mediated banana protoplast transformation system can serve as a rapid and effective tool for transient expression assays and sgRNA validation in banana.The application of CRISPR/Cas9 RNPs system enables the generation of DNA-free genome edited banana plants.