Mu MADS 1 and Ma OFP 1 regulate fruit quality in a tomato ovate mutant

Summary Fruit ripening and quality are common botanical phenomena that are closely linked and strictly regulated by transcription factors. It was previously discovered that a banana MADS ‐box protein named Mu MADS 1 interacted with an ovate family protein named Ma OFP 1 to regulate banana fruit ripening. To further investigate the role of Mu MADS 1 and Ma OFP 1 in the regulation of fruit quality, a combination of genetic transformation and transcriptional characterization was used. The results indicated that the co‐expression of Mu MADS 1 and Ma OFP 1 in the ovate mutant could compensate for fruit shape and inferior qualities relating to fruit firmness, soluble solids and sugar content. The number of differentially expressed genes ( DEG s) was 1395 in WT vs. ovate , with 883 up‐regulated and 512 down‐regulated genes, while the numbers of DEG s gradually decreased with the transformation of Mu MADS 1 and Ma OFP 1 into ovate. ‘ Starch and sucrose metabolism’ constituted the primary metabolic pathway, and the gene numbers in this pathway were obviously different when Mu MADS 1 and Ma OFP 1 were integrated into ovate . A series of metabolic genes involved in cell wall biosynthesis were up‐regulated in the WT vs. ovate , which probably resulted in the firmer texture and lower sugar contents in the ovate fruit. These results demonstrate that Mu MADS 1 and Ma OFP 1 are coregulators of fruit quality, facilitating the dissection of the molecular mechanisms underlying fruit quality formation.