Body Language of Firefly Put Into Body Language of Plants : Study Aimed at Genetic Understanding, Better Crops

Molecular geneticist David Ow explains his laboratory full of test tubes, labyrinthine machines and rows of small clear plastic boxes, each holding a different sized tobacco plant, very simply:

“We’re taking the body language of the firefly and putting it into the body language of the plant,” Ow said, smiling from ear to ear, as he showed reporters around a section of the recently dedicated Plant Gene Expression Center at the U.S. Department of Agriculture western research center.

But Ow’s research and that of other scientists at the center is actually extremely complicated.

The center, opened in 1984 as a joint project of the USDA, the University of California at Berkeley and the Califorina Agricultural Experiment Station, explores the genetic structure of agricultural plants in order to understand and improve the genetic makeup of subsequent generations of crops.

Researchers say they want to know how genes are expressed--”turned on or turned off”--in a plant, so they can know how instructions contained within the gene are executed by the plant.

By taking the mechanism that causes a firefly to emit light, known as the luciferase enzyme, and introducing it in a tobacco plant, Ow said he can observe how and when genetic changes occur in growing plants. Eventually this capability is expected to help researchers control the changes and rate of change.

Improved Nutritional Value

When scientists are able to control genetic changes in agricultural plants such as corn, wheat and tomatoes they hope then to be able to improve nutritional value, control ripening and improve baking qualities.

For his research, Ow has isolated bits and pieces of tobacco plants in separate plastic boxes, where they regenerate into whole plants. Variations in the genes of the plant are observed with the luciferase enzyme.

“This gene works like a light bulb--an indicator light,” Ow said. “Whenever the enzyme causes the light emitting reaction it indicates a chemical reaction,” he said.

“It doesn’t glow enough to see with naked eye, unless you go into dark room for 20 minutes so your eyes can adjust to the light. Then you can see the roots glowing,” Ow said.

“But we can capture the light on film and the image tells us where genes are turned on,” he said.

Another researcher at the center, Athanasios Theologis, has been working with the ripening agent in fruit, known as ethylene, to understand how it works and how it can be regulated.

Half of Crops Lost

“Fifty percent of crops are lost because of this molecule and we can’t afford that anymore,” he said.

Using the stem of a pea plant for a biological model, Theologis studies the activity of the genes that affect the regulation of ethylene.

“We don’t know how this works, but we would like to be able to control ripening (by ethylene) at the molecular level--to initiate fruit ripening at will,” he said.

Other research at the gene center includes the study of mutation patterns in corn to understand how genes control leaf development and how photosynthesis might be regulated.

“Our goal is to provide a new technology that will better serve the needs of agriculture,” said Gerald G. Still, director of the gene center.