Scientists at Washington University School of Medicine in St. Louis are part of a team that has generated the first complete DNA sequence of a plant. The team sequenced the genome of Arabidopsis thaliana, a flowering mustard.
Because Arabidopsis is a widely studied model organism, its sequence will enable scientists to study genes that control basic plant functions. This knowledge will be useful for improving important crops such as wheat, corn and soybeans. It also will aid the ongoing effort to identify genes in the human sequence.
The milestone is reported in the Dec. 14 issue of Nature. The Arabidopsis Genome Initiative, an international consortium, performed the research. All data are freely available on the Internet. Under the direction of Richard K. Wilson, Ph.D., associate professor of genetics, the School of Medicines Genome Sequencing Center played a two-part role in the project. During the early stage, it constructed a genome map that was used by all the sequencing centers. In collaboration with Cold Spring Harbor Laboratory in New York State and the John Innis Centre in the United Kingdom, it then sequenced chromosomes 4 and 5. Arabidopsis has five chromosomes in all.
Arabidopsis is a small plant that grows readily in the laboratory. Its unusually compact genome has just 125 million base pairsthe building blocks of the genomecompared with wheats 15 billion. Both plants have approximately the same number of genesArabidopsis has 25,498, the researchers discoveredbut wheat contains many more repeated sequences.
Information gained from the sequence may provide a basis for improving important crop plants through breeding or genetic engineering. Such improvements might include foods that last longer on supermarket shelves, are lower in fat or higher in protein or tastier.
It may also help make crops hardier. Analysis of the sequence suggests that cell signaling pathways that respond to bacteria, parasites and other external threats ar
Contact: David Linzee
Washington University School of Medicine