UNIVERSITY PARK, Pa. -- A molecular geneticist in Penn State's College of Agricultural Sciences was instrumental in the creation of a U.S. Department of Energy (DOE)-funded, ground-breaking effort to sequence the genome of the poplar tree.

"This is the most exciting event that has ever happened in the field of tree molecular genetics," says John Carlson, associate professor of molecular genetics in the School of Forest Resources.

"I have never seen the forest genetics community more excited," says Toby Bradshaw, of the University of Washington, one of the world's foremost tree molecular geneticists.

Bradshaw helped lay the foundation for the project through his discovery of the female cottonwood tree that was chosen for sequencing. Named "Nisqually-1," the tree has been the focus of intensive genetics and physiology studies, and is one of the most successful parent trees for hybrid poplar production.

So what is it about such a seemingly obscure, esoteric tree research project that is so important and exciting? And why the poplar tree (genus Populus)?

"The genome sequence of Populus trichocarpa (cottonwood) is expected to lead to faster-growing trees that produce more biomass for conversion to fuels and paper," explains Carlson. "In addition, trees with unique traits may be useful in phytoremediation, a process whereby trees such as cottonwoods or hybrid poplars could be used to clean up hazardous waste sites."

According to Carlson, Populus trees like cottonwood, hybrid poplar and aspen have emerged as model organisms in forestry for the same reasons that Populus was chosen as the first tree genome to sequence -- rapid growth rate, small genome size and widespread use in plantation forestry and other areas of interest to the forest industry and the DOE.

Cottonwoods, hybrid poplars and aspens also could play a role in improving the environment, displacing imported oil and creating domestic jobs. But first scientists need to better understand the biology of Populus, for which the genome sequence will provide the blueprint.

This project builds upon the success that the DOE has had in mapping the human genome, a decade-long effort that is expected to lead to cures and the prevention of diseases in people. While sequencing the human genome took years, researchers at the Joint Genome Institute at the DOE's Oak Ridge National Laboratory in Tennessee and cooperating institutions expect to make the genetic blueprint of Populus available within 18 months. And they expect the payback to be significant.

"This effort will furnish scientists in this country and abroad with an unprecedented molecular 'parts list' for a tree," said Jerry Tuskan, the lead Populus genetics researcher in Oak Ridge National Lab's Environmental Sciences Division. "Such a list will provide the scientific community with a catalog of genes, knowledge as to what these genes do in trees and an exciting opportunity to better understand how trees grow."

"The information we gain from this effort will open the doors to countless other opportunities to use woody plants in the production of new and traditional forest products and even in ecological preservation," says Carlson. "The sequencing of the poplar genome will be a bonanza for researchers seeking to understand how individual genes influence the growth of trees and their adaptation to the natural environment. This knowledge eventually might be applied to the breeding of fast-growing trees capable of producing wood, fiber and energy on a smaller amount of land."

Worldwide, support for the project is high, according to Carlson, as more than 100 scientists have indicated via a Web survey that they believe a poplar tree genome sequencing effort should be a top priority of forest research. Already, cottonwoods, hybrid poplars and aspens are being used in a variety of ways ranging from paper production to carbon sequestration to the development of fast-growing trees as a source of feedstocks for renewable bio-based products.

Carlson describes his role in the project this way: "After I gave a talk in December of 2000, David Luke, former CEO of the forest industry giant Westvaco and a native of Tyrone, Pa., suggested that I prepare a case statement describing the need for and benefits of sequencing the poplar genome. I did, and that document started a wider discussion of the concept among forest geneticists, but none of us imagined that within a few months the project might become a reality. My colleagues Bradshaw and Tuskan turned the ideas in the case statement into a great proposal that the DOE quickly adopted."

Carlson serves on a steering committee for the International Poplar Genome Consortium, which is helping DOE chart a path for the sequencing effort and facilitate public access and use of the data. Participants in the consortium include the DOE's Oak Ridge National Laboratory, the DOE°s Joint Genome Institute, Genome Canada, The Swedish Populus Genome Project, Penn State, Oregon State, Michigan State and the University of Washington.

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EDITORS: Contact John Carlson at 814-863-7561 or e-mail jec16@psu.edu.

Contact:

Jeff Mulhollem jjm29@psu.edu 814-863-2719 814-865-1068 fax