Tomato Transcription Factor Plays an Important Role in Tomato Flower and Locule Development.

Tomato is a model species for fleshy fruit development. The shapes and sizes of tomato () are mainly controlled by several loci, including locule number (). Two single nucleotide polymorphisms were found downstream of () in a putative tomato CArG -regulatory element. The mutation may affect the binding of (), cause the up-regulation of and result in increased locule numbers. In this study, tissue expression levels showed that is expressed in young floral buds and shoot apexes. Silencing on an mutant genetic background with an RNA interference (RNAi) strategy resulted in smaller flowers and fruit than those of the wild-type plants, with decreased locule number. Further study revealed that the RNAi lines exhibited altered expression levels of the and genes that participate in the regulation of tomato flower and fruit locule development. In conclusion, this study provides the first genetic evidence that may be the candidate gene of the locus and reveals the function of in flower development.