The CRISPR-based gene editing technology has become more and more powerful in genome manipulation for agricultural breeding, with numerous improved toolsets springing up. In recent years, many CRISPR toolsets for gene editing, such as base editors (BEs), CRISPR interference (CRISPRi), CRISPR activation (CRISPRa), and plant epigenetic editors (PEEs), have been developed to clarify gene function and full-level gene regulation. Here, we comprehensively summarize the application and capacity of the different CRISPR toolsets in the study of plant gene expression regulation, highlighting their potential application in gene regulatory networks' analysis. The general problems in CRISPR application and the optimal solutions in the existing schemes for high-throughput gene function analysis are also discussed. The CRISPR toolsets targeting gene manipulation discussed here provide new solutions for further genetic improvement and molecular breeding of crops.
Keywords: CRISPR; CRISPR toolsets; crop improvement; gene function analysis.