Genome-Wide Identification, Expression Profile and Evolution Analysis of Importin α Gene Family in Glycine max

Importin α (IMPα) proteins are key mediators of nucleocytoplasmic transport and play crucial roles in plant development and stress adaptation. Here, we performed a genome-wide identification of the IMPα gene family in Glycine max, followed by gene structure and conserved motif analyses, chromosomal distribution and duplication inference, synteny and selection (Ka/Ks) analyses, and expression profiling across tissues and stress conditions using public RNA-seq datasets and expression browsers. The GmIMPα genes exhibited diverse gene structures and conserved motifs, suggesting functional diversification within the family. Segmental duplication was identified as the main contributor to family expansion, and most duplicated gene pairs underwent purifying selection. Promoter analysis revealed numerous stress- and hormone-responsive cis-elements, implying complex transcriptional regulation. Expression profiling demonstrated that GmIMPα5 and GmIMPα7 were strongly induced under drought, heat, and salt stresses, indicating potential roles in abiotic stress tolerance. Collectively, our results provide a comprehensive framework for the evolution and functional divergence of the GmIMPα family in soybean and offer candidates for improving stress resilience.