Genome-wide identification and expression analysis of the SPL transcription factor family and its expression characteristics in Elymus sibiricus.

Background: Elymus sibiricus is widely utilized for establishing of high-yield artificial grasslands due to its remarkable productivity and strong resistance to environmental stresses, making it an excellent forage species. SPL transcription factors play a pivotal role in regulating plant growth, development, and responses to abiotic stress. Although the SPL gene family has been identified in many plant species, its presence and function in E. sibiricus remain largely unexplored.

Result: This study presents a comprehensive genome-wide identification and analysis of the SPL gene family in E. sibiricus. A total of 37 EsSPL genes were successfully identified. Their chromosomal distribution, gene structure, conserved motifs, cis-acting regulatory elements, and evolutionary relationships were analyzed. Protein-protein interaction network analysis predicted that SOC1 and TOE2 are the primary interacting proteins. Most EsSPL genes exhibited high expression levels in seedling tissues. Additionally, analysis of abiotic stress responses revealed that the expression of multiple EsSPL genes was altered under salt, drought, abscisic acid (ABA), and gibberellin (GA) treatments.

Conclusion: Through sequence homology analyses, 37 SPL genes were identified in E. sibiricus. Most SPL family members exhibited high expression levels in seedling tissues, with EsSPL2 specifically upregulated under four distinct abiotic stress conditions. These findings provide a foundation for understanding the genetic evolution and biological functions of the SPL gene family in E. sibiricus, offering valuable insights for future research and breeding efforts.