The SBP transcription factor SPL10 regulates leaf curvature by promoting REVOLUTA transcription in plants. The SBP transcription factor SPL10 regulates leaf curvature by promoting REVOLUTA transcription in plants

The developmental functions of SQUAMOSA PROMOTER BINDING PROTEIN-LIKE (SPL) 10 have been extensively studied in Arabidopsis, but SPL10's role in regulating leaf curvature has not been well characterized. In this study, we observed an upward-curling leaf phenotype upon overexpression of a miR156/157-resistant version of SPL10 (rSPL10). DNA affinity purification sequencing (DAP-seq), RNA-seq, and transient transactivation assays revealed that SPL10 binds to the promoter of REVOLUTA (REV). Consistent with binding assays, overexpression of a miR165/166-resistant version of REV (rREV) in WT plants caused an upward-curling leaf phenotype. Conversely, overexpression of rSPL10 in a rev-6 mutant couldn't rescue the downward-curling leaf phenotype of rev-6. Notably, SPL10 physically interacts with REV, attenuating the upward-curling leaf phenotype of rREV mutants, suggesting a role as a molecular rheostat to prevent overamplification of REV transcripts. Furthermore, overexpression of the BrpREV-1 gene caused rosette leaves to change from flat to upward curving and accelerated heading in Chinese cabbage. Taken together, our findings identify the role of the SPL10-REV module in regulating leaf curvature in Arabidopsis and the crucial functions of BrpREV-1 in the heading of Chinese cabbage. Overall design: DAP-seq to identify the dirctely target genes of SPL10.