Integrative Bioinformatic Analysis of NHX Genes in Spinacia oleracea L.: From Chromosomes to Stress-Responsive Regulation

TL;DR

This study explores how NHX genes in spinach help plants cope with environmental stresses like drought and cold.

Contribution

The study identifies 44 NHX genes in spinach and reveals their roles in stress response and regulation.

Findings

44 NHX genes were identified in Spinacia oleracea with detailed chromosomal and structural analysis.

SoNHX14, SoNHX20, and SoNHX33 are central regulators in stress response mechanisms.

NHX genes are regulated by stress-associated miRNAs at the post-transcriptional level.

Abstract

Background/Objectives: The NHX gene family plays a critical role in regulating ion homeostasis and enhancing plant tolerance to abiotic stresses. This study aimed to comprehensively analyze the structural, phylogenetic, and functional characteristics of the NHX gene family in the genome of Spinacia oleracea L. Methods: Through bioinformatic approaches, a total of 44 NHX genes were identified, and their chromosomal distribution, exon-intron organization, and conserved motifs were thoroughly characterized. Protein-protein interaction network analysis revealed that SoNHX14, SoNHX20, and SoNHX33 act as central regulators, playing key roles in cellular stress response mechanisms. Furthermore, the majority of SoNHX proteins were predicted to localize primarily to the plasma membrane, endoplasmic reticulum, and vacuole. Promoter analyses indicated a widespread presence of cis-acting elements responsive to stresses such as low temperature, drought, and wounding, as well as elements responsive to plant hormones, suggesting a complex and multilayered regulatory mechanism. Results: miRNA target predictions demonstrated that NHX genes are extensively regulated at the post-transcriptional level, predominantly by stress-associated miRNA families. Conclusions: These findings support a central role for the NHX gene family in abiotic stress adaptation in S. oleracea and provide a valuable foundation for future genetic interventions aimed at improving stress tolerance.

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