Engineering Diversified Allelic Variation in Maize by Fragment Knockout Using CRISPR/Cas9 Genome Editing
Engineering allelic variation by CRISPR/Cas9 gene editing technology has become an impor-tant mean to increase germplasm resources diversity in many plants.Increasing the content of carotenoids in ce-reals such as maize is an economic approach to solve vitamin A deficiency in developing countries.In this stud-y,the crtRB1 gene regulating carotenoid synthesis in maize was chosen as subject,the CRISPR/Cas9 dual-target system was used to perform fragment deletion on the promoters of crtRB1 in maize protoplasts,and then new diversified allelic variations with fragment deletion and InDel(insertion or deletion)were engineered.The results laid a foundation for the engineering of mutations in crtRB1 promoters and was of great significance to the functional research of promoter elements and improvement of maize quality.