Species-Specific MiRNAs Contribute to the Divergence Between Deciduous and Evergreen Species in

MicroRNAs (miRNAs) are pivotal regulators of gene expression, playing crucial roles in plant developmental processes and environmental responses. However, the function of miRNAs in influencing deciduous traits has been little explored. Here, we utilized sRNA-seq on two deciduous species, (Hand.-Mazz.) S. Y. Hu and Champ. ex Benth., along with an evergreen species, Thunb., to identify and annotate miRNAs within these species. Our analysis revealed 162 species-specific miRNAs (termed SS-miRNAs) from 120 families, underscoring the fundamental roles and potential influence of SS-miRNAs on plant phenotypic diversity and adaptation. Notably, three SS-miRNAs in were found to target crucial genes within the abscission signaling pathway. Analysis of -regulatory elements suggested a novel regulatory relationship that may contribute to the evergreen phenotype of by modulating the abscission process in a light-independent manner. These findings propose a potential mechanism by which SS-miRNAs can influence the conserved abscission pathway, contributing to the phenotypic divergence between deciduous and evergreen species within the genus .