Promoter editing for the genetic improvement of crops

Gene expression plays a fundamental role in the regulation of agronomically important traits in crop plants. The genetic manipulation of plant promoters through genome editing has emerged as an effective strategy to create favorable traits in crops by altering the expression pattern of the pertinent genes. Promoter editing can be applied in a directed manner, where nucleotide sequences associated with favorable traits are precisely generated. Alternatively, promoter editing can also be exploited as a random mutagenic approach to generate novel genetic variations within a designated promoter, from which elite alleles are selected based on their phenotypic effects. Pioneering studies have demonstrated the potential of promoter editing in engineering agronomically important traits as well as in mining novel promoter alleles valuable for plant breeding. In this review, we provide an update on the application of promoter editing in crops for increased yield, enhanced tolerance to biotic and abiotic stresses, and improved quality. We also discuss several remaining technical bottlenecks and how this strategy may be better employed for the genetic improvement of crops in the future. This review provides an update on the application of promoter editing in modulating diverse biological processes in plants, highlights major remaining challenges in crop promoter editing, and discusses promising breakthrough strategies.

Automated summary

Gene expression plays a crucial role in crop plant regulation. Genome editing of plant promoters offers the potential to modify gene expression patterns and create favorable traits. This can be done by precise generation of nucleotide sequences or by generating random mutations in the promoter region to select elite alleles based on phenotypic effects.