Gene for bitterness in cucumbers identified
The research, published in the U.S. journal Science, revealed how cucumbers, believed native to India, were domesticated from their wild ancestors that have extremely bitter fruits to make them more edible.
Today's domestic cucumbers are delicious, stress conditions such as a lack of water or temperatures too cold or too hot, however, are still able to cause them to bear bitter tasting fruits, Huang said.
In the new study, Huang and colleagues performed genomic and biochemical analyses on 115 diverse cucumber lines to unravel the biosynthetic pathway involved in domesticating cucumbers to the non-bitter fruits people eat today.
They were able to identify nine genes involved in making cucurbitacins, which confer a bitter taste in cucumbers, and showed that the trait can be traced to another two genes that switch on these nine genes to produce the compounds.
In short, bitterness is controlled by two "master switch" genes, "Bl" which confers bitterness in leaves and "Bt", which leads to bitter fruit, Huang said.
The study also found that a mutation in the Bt gene is able to keep domestic cucumbers from becoming bitter even when exposed to stress conditions such as cold temperatures.
Source: xinhuanet.com