Enhancing grain-yield-related traits by CRISPR-Cas9 promoter editing of maize CLE genes (Nature Plants)

During domestication of maize, one of the favorable traits was meristem size. Understanding the genetic circuit of maize meristem development and engineering for crop productivity are important from an agricultural perspective. In this article, Lie et al. used CRISPR-Cas9 to edit the promoter regions of ZmCLE7 (ZmCLAVATA3/EMBRYO SURROUNDING REGION-RELATED7), ZmFCP1 (ZmFON2-LIKE CLE PROTEIN1) and coding regions of ZmCLE1E5 to generating weak or null alleles, respectively. They eventually generated 13 alleles: six for ZmCLE7, five for ZmFCP1, and two for ZmCLE1E5. The promoter edited alleles of ZmCLE7 and coding region-edited alleles of ZmCLE1E5 have larger inflorescence meristem (IMs) diameters. Additionally, the authors found that these alleles have increased kernel row numbers and grain yields. This work highlights CRIPSR-Cas9-mediated gene editing as a tool to modify agriculturally important traits such as meristem size in maize. (Summary by Arif Ashraf) Nature Plants 10.1038/s41477-021-00858-5