Divergent Roles of SOG Family Genes in Salt Tolerance: A Comparative Genomics Study Between Barley and Rice.

Area of Science:

• Plant Molecular Biology
• Genomics
• Stress Physiology

Background:

• Salt stress significantly limits global agricultural yield.
• Suppressor of gamma response (SOG) genes are crucial for plant DNA repair and abiotic stress adaptation.
• Limited research exists on SOG gene functions in barley and rice, vital cereal crops.

Purpose of the Study:

• To conduct the first genome-wide identification and comparative analysis of the SOG gene family in barley and rice.
• To investigate the roles of SOG genes in differential salt tolerance mechanisms between these two crops.

Main Methods:

• Genome-wide identification of SOG genes in barley (97 HvSOGs) and rice (74 OsSOGs).
• Comparative analysis of gene structures, motifs, duplication, and cis-elements.
• Analysis of SOG gene expression patterns under salt stress and functional validation of OsSOG17.

Main Results:

• Significant variations in gene structure, motifs, duplication, and cis-elements were observed between barley and rice SOGs.
• Barley exhibits a higher proportion of SOGs with stress-related cis-elements and an energy-saving strategy in shoots under salt stress.
• Gene loss and functional divergence in rice may contribute to its salt sensitivity, while OsSOG17 positively regulates salt tolerance.

Conclusions:

• Barley's superior salt tolerance is linked to an energy-saving strategy in shoots.
• Evolutionary processes like gene loss and functional divergence impact salt sensitivity in rice.
• The study functionally links SOG genes to salt stress responses and uncovers potential mechanisms for differential salt tolerance.