Genome-wide identification and expression analysis of the SAUR gene family in foxtail millet (Setaria italica L.)

BackgroundAuxin performs important functions in plant growth and development processes, as well as abiotic stress. Small auxin-up RNA (SAUR) is the largest gene family of auxin-responsive factors. However, the knowledge of the SAUR gene family in foxtail millet is largely obscure.ResultsIn the current study, 72 SiSAUR genes were identified and renamed according to their chromosomal distribution in the foxtail millet genome. These SiSAUR genes were unevenly distributed on nine chromosomes and were classified into three groups through phylogenetic tree analysis. Most of the SiSAUR members from the same group showed similar gene structure and motif composition characteristics. Analysis of cis-acting elements showed that many hormone and stress response elements were identified in the promoter region of SiSAURs. Gene replication analysis revealed that many SiSAUR genes were derived from gene duplication events. We also found that the expression of 10 SiSAURs was induced by abiotic stress and exogenous hormones, which indicated that SiSAUR genes may participated in complex physiological processes.ConclusionsOverall, these results will be valuable for further studies on the biological role of SAUR genes in foxtail development and response to stress conditions and may shed light on the improvement of the genetic breeding of foxtail millet.

Automated summary

In this study, 72 SiSAUR genes were identified and named according to their chromosomal distribution in the foxtail millet genome. These genes were classified into three groups based on phylogenetic tree analysis, and showed similar gene structure and motif composition characteristics within each group. Analysis of cis-acting elements in the promoter region revealed the presence of hormone and stress response elements. Gene replication analysis indicated that many SiSAUR genes were derived from gene duplication events. Furthermore, the expression of 10 SiSAUR genes was induced by abiotic stress and exogenous hormones, suggesting their involvement in complex physiological processes.