FAS, YABBY2, and YABBY5 Gene Expression Profile Correlates with Different Fruit Locule Number in Tomato

Analysis of 30 tomato cultivars with different fruit locule numbers revealed four cultivars with multi-locular fruits carrying a null mutation in the SlFAS gene. It was shown that cultivars with more than two fruit locules contain two SNPs, associated with the multi-locule trait, at the locule number locus. Co-expression profile of SlFAS, SlYABBY2 and SlYABBY5 genes was determined in a young bud and at three stages of fruit development in three tomato cultivars contrasting in the fruit locule number. In the Cœur de bœuf cultivar (≥10 locules), SlFAS transcripts were absent in all analyzed tissues. In addition, compared with the Red Cherry (2 locules) and Viking (5–6 locules) cultivars, in the Cœur de bœuf bud and fruits, the transcription levels of SlYABBY2 and SlYABBY5 were considerably lower and higher, respectively.