LA JOLLA, Calif., May 4 (UPI) -- Biologists have known plants "pump up" when given extra amounts of the plant steroid brassinolide, but until a recent U.S. study they didn't know how.
Tracing brassinolide's signal deep into the cell's nucleus, researchers at the Salk Institute for Biological Studies say they've discovered how the growth-boosting hormone accomplishes its job at the molecular level.
"The steroid hormone brassinolide is central to plants' growth. Without it, plants remain extreme dwarfs. If we are going to understand how plants grow, we need to understand the response pathway to this hormone," said study leader Joanne Chory, a professor of plant molecular and cellular biology, and a Howard Hughes Medical Institute investigator.
Brassinolide, a member of a family of plant hormones known as brassinosteroids, enables plants to adjust their growth to reach light or strengthen stems. Exploiting its potent growth-promoting properties could increase crop yields or make plants more resistant to drought, pathogens, and cold weather, scientists said.
Although synthesizing brassinosteroids is complicated and expensive, the researchers say understanding how plant steroids work may one day lead to cheap and simple ways to bulk up crop harvests.
The research appears in the journal Nature.