Abstract
The BES1/BZR1 transcription factors regulate the expression of genes responsive to brassinosteroids and play pivotal roles in plant development, but their role in regulating kernel development in maize remains unclear. In this study, we found that ZmBES1/BZR1-5 positively regulates kernel size. Association analysis of candidate genes in 513 diverse maize inbred lines indicated that three SNPs related to ZmBES1/BZR1-5 were significantly associated with kernel width and whilst four SNPs were related to 100-kernel weight. Overexpression of ZmBES1/BZR1-5 in Arabidopsis and rice both significantly increased seed size and weight, and smaller kernels were produced in maize Mu transposon insertion and EMS mutants. The ZmBES1/BZR1-5 protein locates in the nucleus, contains bHLH and BAM domains, and shows no transcriptional activity as a monomer but forms a homodimer through the BAM domain. ChIP-sequencing analysis, and yeast one-hybrid and dual-luciferase assays demonstrated that the protein binds to the promoters of AP2/EREBP genes (Zm00001d010676 and Zm00001d032077) and inhibits their transcription. cDNA library screening showed that ZmBES1/BZR1-5 interacts with casein kinase II subunit β4 (ZmCKIIβ4) and ferredoxin 2 (ZmFdx2) in vitro and in vivo, respectively. Taken together, our study suggests that ZmBES1/BZR1-5 positively regulates kernel size, and provides new insights into understanding the mechanisms of kernel development in maize.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
