Characterization of SPL Family Genes in Banana Reveals the Critical Role of MaSPL1 in Regulating Fruit Ripening

SPLs (SQUAMOSA promoter binding protein-like) are pivotal in regulating plant development and stress responses. Although SPL genes have been characterized in a series of plant species, no systematic analysis has been performed on bananas, one of the most consumed tropical fruits with immense economic importance worldwide. Here, 55 putative MaSPL genes were identified in Musa acuminata ssp. malaccensis var. Pahang and classified into seven groups based on phylogenetic analysis. The RNA-seq analysis revealed that the expression of MaSPLs presented distinct spatiotemporal patterns in different tissues at different developmental stages, indicating a potential role in banana growth and development. Furthermore, MaSPL1 was found to be predominantly expressed in banana fruits during the fruit development and the early postharvest stages. Notably, the transient overexpression of MaSPL1 accelerated the fruit ripening in bananas. In conclusion, this study provides comprehensive information for further investigation of the specific roles of SPL genes in banana developmental processes, particularly during fruit development and post-harvest stages, and may implement molecular strategies to regulate maturation and enhance fruit quality in bananas.