Athens, Ga. – Researchers at the University of Georgia have won a $1.34 million grant from the U.S. Department of Energy to attempt to increase the productivity of trees by genetically modifying certain proteins critical to wood formation. The study could have important implications in using trees as biofuel.
The research will be conducted by Scott Harding and Chung-Jui Tsai, who are both faculty members at UGA’s Warnell School of Forestry and Natural Resources.
They became interested in the possibility that manipulating sucrose transporter proteins-which shuttle food from leaves throughout the rest of the tree-during a separate, unrelated project conducted by Raja Payyavula, a graduate student working for the pair. The student’s research led to the discovery of a connection between sucrose transporter genes and certain stimuli.
Sucrose transporter genes have been known about for a long time because they enable leaves to send the sugars they produce during photosynthesis to other parts of the growing plant that do not carry out photosynthesis. This would include grain or tubers in food crops. In a key, and somewhat surprising finding by Harding and Tsai, sucrose transporter genes were found to be very abundant in developing the wood of young trees. They now want to know how a tree will react-positively or negatively-to further modification of those proteins.
They hope that tweaking the proteins will modify the way trees divide their photosynthate (sucrose and other sugars) between wood-forming and other organs like roots and bark. Wood is the raw feedstock for biofuels, and the research is being funded to learn about the potential of this gene for affecting wood growth, and thus tree growth, under a variety of environmental conditions.
“We know there’s a connection,” said Harding. “We just don’t know much about that connection right now.”
The research team already has begun its experiments with the award from the joint Plant Feedstock Genomics 2010 program from the U.S. Department of Agriculture and DOE. This program funds projects that accelerate plant breeding and improve biomass feedstocks to lay the groundwork for a new class of biofuels that are low-cost, high-quality and maximize the amount produced per acre.
More information about the Plant Feedstock Genomics for Bioenergy program can be found at http://genomicscience.energy.gov/.
In announcing the award-which is part of the Obama administration’s efforts to diversify the nation’s energy portfolio and accelerate the development of new energy technologies-leaders of the two funding federal agencies commented on their hopes that such research will help reduce the U.S.’s dependence on foreign oil.
“Cost-effective, sustainable biofuels are crucial to building a clean energy economy,” said Secretary of Energy Steven Chu. “By harnessing the power of science and technology, this joint effort between DOE and USDA will help accelerate research in the critical area of plant feedstocks, spurring the creation of the domestic bio-industry while creating jobs and reducing our dependence on foreign oil.”
“Developing a domestic source of renewable energy will create jobs and wealth in rural America, combat global warming, replace our dependence on foreign oil and build a stronger foundation for the 21st century economy,” said Secretary of Agriculture Tom Vilsack. “This scientific investment will lay the foundation for a source of fuel made from renewable sources.”
The $1.34 million grant is part of a larger, $9 million grant package awarded to multiple agencies and universities across the U.S.
Harding, senior research scientist, and Tsai, a professor Georgia Research Alliance Eminent Scholar who also has a joint appointment in the department of genetics, joined the Warnell School in 2008. Their work focuses on forest biotechnology with an emphasis on creating high-energy trees for use in biofuel.
Tsai’s interests also include determining how trees defend themselves by using chemical compounds to ward off bugs and grazing animals. Harding also has led a DOE-research project on carbon sequestration, where carbon dioxide emissions from facilities such as power plants are captured by trees rather than released into the atmosphere.
If they are successful in genetically modifying the sucrose transporter genes to create faster-growing trees, it could have tremendous implications for using trees as biofuels.
“We know the sucrose transporter genes are connected to tree growth, and we also know that there are three different such proteins present in the tree stems,” Harding explained. The team plans to manipulate those proteins to learn about their division of labor and to see how the manipulations affect tree growth, especially the competition between leaves, stems and roots for photosynthate. The project will involve an assistant research scientist, a postdoctoral scientist, two graduate students and several undergraduate students.
This investigation is just beginning, Tsai said, and findings during the course of this three-year project will add immensely to the understanding of how tree biomass is produced.
