Genome-Wide Identification and Characterization of Tomato Acyl-CoA Oxidase Family Genes ACX

This study conducted a systematic identification and functional analysis of the SlACX gene family in Solanum lycopersicum. Through genome-wide screening, a total of six SlACX members were identified, and their encoded proteins showed significant differences in physicochemical properties, suggesting potential functional differentiation. Analysis of gene structure and conserved motifs revealed that SlACXs were highly conserved in evolution, but the cis-acting elements in the promoter region were rich and diverse, suggesting that they may integrate multiple signaling pathways. Chromosomal localization and collinearity analysis revealed that gene replication events were the main driving force for family expansion, and there were key interspecific collinearity blocks with Arabidopsis thaliana and Glycine max. Expression analysis showed that SlACXs exhibited remarkable tissue specificity and strong temporal dynamic response patterns to UV, dark, ABA, MeJA, and various abiotic stresses (cold, heat, H2O2, PEG, and NaCl). Several genes (such as SlACX1, SlACX3, SlACX4, and SlACX5) exhibited consistently high expression levels under various stress conditions, underscoring their potential role as central regulatory hubs.