Molecular and functional analyses of aldolase and eukaryotic translation initiation factor genes in olive (Olea europaea L.)

Objective: This study aimed to elucidate the molecular basis of stress tolerance and metabolic regulation in olive by characterizing two genes: fructose-1,6- bisphosphate aldolase (OeFBPA) and eukaryotic translation initiation factor 4E (OeEIF4E).Material and Methods: The OeFBPA and OeEIF4E genes were analyzed using genomic, transcriptomic, and proteomic approaches. Bioinformatic tools were employed to determine protein properties and promoter elements. Gene expression was assessed in different olive tissues by qRT-PCR. Recombinant proteins were expressed in Escherichia coli (E. coli) and validated using SDS- PAGE, silver staining, and Western blotting.Results: Both genes encoded soluble, cytoplasmic, and highly conserved proteins lacking transmembrane domains and signal peptides. OeFBPA retained the catalytic lysine typical of Class I aldolases, whereas OeEIF4E retained the canonical cap-binding domain. Promoter analysis revealed stress- and light-responsive cis-elements. OeFBPA showed the highest expression in flowers, followed by pedicels and on-year leaves, while OeEIF4E was strongly enriched in on-year leaves.Conclusion: OeFBPA and OeEIF4E play complementary roles in carbon metabolism and translational regulation, thereby contributing to stress adaptation in olive trees. This study provides the first comprehensive characterization of these genes in Olea europaea.