For many people summer equals tomatoes. That’s when folks can get their hands on gorgeous heirloom and traditional varieties, full of tomatoey flavor. Such tomatoes provide a stark contrast to year-round supermarket ones, famous for tasting like, well, nothing. They’ve been bred for uniform color and ripening—not for taste.
Now scientists have determined just what’s genetically missing in store-bought tomatoes.
The researchers honed in on two transcription factors. Transcription factors are proteins that control the expression of genes—in this case they’re necessary for the production of chloroplasts, which allow sunlight to generate sugars and other compounds.
Darker green tomato fruit expresses genes that make possible increased photosynthesis—and so the fruits are able to produce more sugars for a tastier end product. But typical supermarket tomatoes, which had been bred to all turn light green at the same time, were also accidentally bred with reduced chloroplasts—and thus reduced sugar content. The research was published in the journal Science. [Ann L.T. Powell et al., "Uniform ripening Encodes a Golden 2-like Transcription Factor Regulating Tomato Fruit Chloroplast Development"]
The scientists say understanding the genes involved in better flavor could enable growers to offer tastier supermarket varieties. So that when you say tomato, I can say to-ma-to or to-mah-to instead of bleech.
[The above text is a transcript of this podcast.]