Genome-wide investigation of genes in and functional characterization of .

The plant-specific SQUAMOSA promoter-binding protein-like (SPL) transcription factors play a pivotal role in various developmental processes, including leaf morphogenesis and vegetative to reproductive phase transition. and are widely used in landscaping due to their tulip-like flowers and peculiar leaves. However, the gene family in has not been identified and systematically characterized. We systematically identified and characterized the family members in , including phylogeny, gene structure and syntenic analyses. Subsequently, we quantified the expression patterns of across various tissue sites through transcription-quantitative polymerase chain reaction (RT-qPCR) assays and identified the target gene, . Finally, we characterized the functions of via ectopic transformation. Altogether, 17 and 18 genes were genome-widely identified in and , respectively. All the 35 were grouped into 9 clades. Both species had three gene pairs arising from segmental duplication events, and the displayed high collinearity with the genome. RT-qPCR assays showed that genes were differentially expressed in different tissues, especially. Because is highly expressed in pistils and leaves, it was selected to describe the gene family of by ectopic expression. We showed that overexpression of in resulted in earlier flowering and fewer rosette leaves. Moreover, we observed that overexpression of in up-regulated the expression levels of four genes related to flower development. This study identified genes in and characterized the function of in advancing flower development.