Gene for sweet tomatoes isolated

Dr. Asaph Aharoni of Israel’s Weizmann Institute recently revealed the gene responsible for producing the sweet, pink-skinned tomatoes preferred by the Far Eastern palate.Aharoni, of the institute’s plant sciences department, conducted research that focuses on plants’ thin, protective outer layers, …

Dr. Asaph Aharoni of Israel’s Weizmann Institute recently revealed the gene responsible for producing the sweet, pink-skinned tomatoes preferred by the Far Eastern palate.

Aharoni, of the institute’s plant sciences department, conducted research that focuses on plants’ thin, protective outer layers, called cuticles, which are mainly composed of fatty, wax-like substances.

In the familiar red tomato, this layer also contains large amounts of antioxidants called flavonoids that are the tomatoes’ first line of defense. Some of these flavonoids also give the tomato cuticles a bright yellow cast – the color component that is missing in the translucent pink skins of the “mutant” tomatoes.

Using a lab system that’s unique in Israel – and one of only a few in the world – along with a multidisciplinary approach known as metabolomics, Aharoni and his team can create a comprehensive profile of substances in mutant plants.

The scientists identified about 400 genes whose activity levels are quite a bit higher or lower in the mutants and found that all these changes can be traced to a mutation on a single gene known as SIMYB12

According to Aharoni, “This ability could accelerate efforts to develop new, exotic tomato varieties.”