Genome-Wide Identification and Expression Analysis of 1-Aminocyclopropane-1-Carboxylate Synthase (ACS) Gene Family in Myrica rubra

Ethylene plays a crucial role in plant growth, development, and stress responses, with 1-aminocyclopropane-1-carboxylate synthase (ACS) being a key enzyme in its biosynthetic pathway. However, the ACS gene family of <i>Myrica rubra</i> has not yet been systematically identified and characterized. In this study, we identified and characterized seven ACS genes (<i>MrACS</i>) in <i>Myrica rubra</i> through genome-wide analysis. Phylogenetic analysis revealed that these genes belong to three major subfamilies, with certain members clustering closely with ACS genes from Rosaceae species, suggesting a conserved evolutionary relationship. Gene structure and the conserved motif analyses confirmed functional conservation, while chromosomal localization indicated an uneven distribution across the genome. Collinearity analysis revealed strong homologous relationships between <i>Myrica rubra</i> and other plant species, particularly <i>Solanum lycopersicum</i>, <i>Vitis vinifera</i>, and <i>Prunus persica</i>. Furthermore, the transcriptome data demonstrated distinct temporal and tissue-specific expression patterns, with <i>MrACS5</i> showing fruit-specific expression, suggesting its potential role in fruit ripening. These findings provide comprehensive insights into the ACS gene family in <i>Myrica rubra</i>, offering a valuable foundation for further functional studies on ethylene biosynthesis and its regulatory mechanisms in fruit development.