Genome-wide analysis of the BES1 gene family reveals their involvement in grain development of Triticum aestivum L.

Background: The BRI1-EMS SUPPRESSOR1 (BES1) gene family was initially recognized as specifically regulating brassinosteroids to mediate gene expression, which is of vital significance for plant growth and enhancing stress tolerance. Despite extensive studies in multiple plants, there has been a lack of focused and systematic analysis of BES1s in wheat grains.

Results: In this study, we performed a comprehensive bioinformatics analysis of the BES1s in wheat, utilizing the latest genomics data from the Chinese Spring. A total of 19 TaBES1 were identified. An analysis of conserved domains, phylogenetic relationships, and gene structure revealed a significant level of conservation among TaBES1s. A gene collinearity analysis indicated that fragment duplication was the primary mechanism responsible for the amplification of TaBES1s. Furthermore, cis-acting elements within the promoters of TaBES1s were found to be implicated in grain development. Subsequently, SNP analysis revealed the genetic variation of TaBES1s across different wheat varieties. Moreover, published RNA-seq data were used, and RNA-seqs of Yaomai36, Pinyu8175, Pinyu8155, and Yaomai30 were performed to identify TaBES1s influencing grain development. Finally, the research found that TaBES1s had no self-activating activity in wheat. However, the interacting proteins of TaBES1-1 and TaBES1-4 are not only involved in starch metabolism but may also be implicated in cell signal transduction.

Conclusions: This study further confirmed the potential function of BES1s in the grain development of wheat. These findings that BES1s play a regulatory role in wheat grain development provide a foundation for further understanding the molecular mechanisms underlying crop grain development.