August 30, 2000
Susan McGinley
Molecular geneticists in the College of Agriculture and Life Sciences are currently studying genes they've already identified in corn to learn more about how those genes are regulated and expressed. Their results, funded by a $10.5 million grant from the NSF in 1999, will assist scientists around the world in breeding and improving crop plants.
"It's a tool-building project," says Vicki Chandler, a molecular geneticist in the Department of Plant Sciences. "We're getting the corn genes into the test tube so we can work with them in a variety of ways to get a better corn plant." This research builds on continuing results from a structural genetics project Chandler began last year to find all 50,000 genes in corn. About 10,000 genes have been identified so far.
"I study gene regulation, how appropriate genes are turned on in the leaves, the flowers, the roots, how genes are turned on in response to environmental signals," Chandler says.
Chandler and Richard Jorgensen, also a molecular geneticist in plant sciences, plan to identify and functionally analyze the genes in both corn and Arabidopsis, a plant in the cabbage family, that contribute to chromatin level control of gene expression. Arabidopsis has a
very small genome, making it simpler to sequence the entire genome, and a fast growth cycle, which makes it convenient to perform genetic experiments.
"We're using Arabidopsis as a starting point and applying it to understand our work with maize," Jorgensen says. Seventy percent of the Arabidopsis genome is currently known, compared to only 20% of corn genes.
Their method takes advantage of a natural gene silencing mechanism in plants that
probably evolved as virus protection in plants. The genes selected for study may only be 1% of the full set of genes, but they are the ones that control the expression of the other 99%.
Chandler and Jorgensen are working with a team of scientists, technicians, undergraduate and graduate students and post-doctoral associates at the UA, and are collaborating with scientists from five other universities on this project.
The team has characterized about 30 Arabidopsis genes so far, and plans to study 130 more Arabidopsis genes and 100 maize genes within the five-year time frame of the study. As they determine the function of each targeted gene, this information is entered into a computer database and becomes accessible to plant breeders, plant genetic engineers and researchers in basic biology around the world who want to know more about how plants work. They can look up gene functions and select only the genes they need to perform certain operations in plants.
- Updated: August 30, 2000
