RNA-seq data of endosperm at 4 DAP

Maize (Zea mays L.) is one of the world’s most important staple crops, and is used for manufacturing food, feed, and industrial products. A key factor in maize yield is the grain weight, which directly influences productivity. In the present study, we revealed the role of smk23 in maize kernel development. The ethyl methanesulfonate mutant smk23 is characterized by substantially reduced kernel weight. Through map-based cloning, smk23 was found to be located on Chr5 and encode a putative B-type response regulator, ZmRR5. A change from G to A occurs in the coding sequence of ZmRR5, resulting in the early termination of smk23.ZmRR5 positively regulates key genes involved in BETL development and function, including MRP1 and TCRR1. Furthermore, RNA sequencing revealed that several genes closely linked to BETL development, including BETL2, MEG1, and MN1, were significantly downregulated in smk23. All raw RNA-seq data have been submitted to NCBI as BioProject PRJNA1165461.