Genes Involved in Giant Tomato Fruit Size Revealed

Tomato varieties usually produce small, berry fruit sized fruits, but apparently, there is a tomato variety that produces a giant fruit weighing over a pound. This variety is called beefsteak tomato, and this ability to produce larger fruit size, makes it different and unusual. The Cold Spring Harbor Laboratory (CSHL) researchers studied the beefsteak tomato to identify the reason behind its large fruit.

In their study, stem cell production is the main reason for its large fruit size. There is an abnormal stem cell proliferation due to the mutation involving CLAVATA3. This gene inhibits stem cell production, and its mutation  result to increase in stem cell number, leading to large fruit size.

With this discovery, the CSHL researchers devised a way to fine-tune growth of beefsteak tomato by changing the number of sugars attached with CLAVATA3 and through another mutation affecting the component of the pathways. This will help breeders in further improving tomato. 

Full details of the study can be read at Cold Spring Harbor Laboratory's website.