Gene that Blocks Lettuce Germination Also Regulates Flowering Time

In a recent study of lettuce and the model plant Arabidopsis, researchers at the University of California Davis Seed Biotechnology Center in the US and in China have shown for the first time that a gene known to direct the depth of seed dormancy and the timing of germination also influences flowering. The study further suggests that the gene does this by influencing the production of certain microRNAs — genetic material that govern the transition from one phase of the plant's life cycle to another.

Co-author Kent Bradford, a plant scientist and director of the Seed Biotechnology Center said it appears that the 'Delay of Germination 1,' or DOG1 gene, is a sensor that detects environmental changes and enables the plant to not only keep the seed dormant, but to also delay flowering. The researchers found that suppressing the DOG1 gene decreased the levels of one microRNA and increased levels of another, resulting to seeds germinating at higher temperatures, and the plants flowering earlier than normal.

"Our results also suggest that the period between seed dormancy and seed germination is a distinct phase in the plant's lifecycle and that this phase appears to be influenced by the same microRNA systems that govern the plant's maturation and flowering stages," said study co-author Heqiang "Alfred" Huo.

For more information about this research, read the news release at the UC Davis website.