The University of Tennessee Research Foundation (UTRF) has executed a non-exclusive license agreement with Amfora, Inc. for a plant-based promoter technology developed by Neal Stewart Jr., Ph.D., professor of plant sciences and Ivan Racheff Chair of Excellence in Plant Molecular Genetics at the University of Tennessee Institute of Agriculture. This promoter has been shown to induce strong gene expression for beneficial traits, such as insect and herbicide resistance, across a variety of grass crops.
Promoters are short pieces of DNA that control gene expression through protein production. They function like switches – when turned on, promoters can induce strong gene expression for a particular trait. Dr. Stewart’s work with promoters grew out of switchgrass genetic engineering research he was conducting at Oak Ridge National Laboratory’s Bioenergy Science Center. His research into using gene manipulation to create plants to yield biofuels led to the discovery of a switchgrass promoter that consistently produced a broad range of gene expression.
“When agricultural companies are working to create a plant that possesses a certain trait, such as resistance to a pathogen, it is beneficial for them to use DNA that is not from the species in question,” says Dr. Stewart. “This switchgrass promoter works well because its gene sequence differs from those already present in grass crops. As a result, you are less likely to encounter gene silencing and more likely to achieve the outcome you want.”
Dr. Stewart’s discovery is notable because few plant-based promoters are available for genetic engineering, and not many promoters possess very strong gene expression (hence, do not produce a lot of protein). As a result, researchers tend to rely on the same promoters over and over. This particular promoter is not only consistent in driving gene expression, but it also does not require an environmental trigger to work (it is “turned on” all the time) and can be successfully inserted into a number of economically important grass crops, like corn, wheat, or sorghum.
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A patent for Dr. Stewart’s promoter technology was issued in December 2013, and a non-exclusive license agreement to use the promoter technology was executed by UTRF in October 2017 with Amfora, Inc. Amfora is an agricultural startup company based in San Francisco, California, that is focused on improving the nutritional content of food and feed crops. Dr. Stewart worked with Michael Lassner, Ph.D., Amfora’s Chief Science Officer, on a grant related to his promoter technology. Dr. Lassner’s familiarity with the technology and its dependability played a role in Amfora’s decision to license the technology.
“Amfora is happy to add the promoters discovered by Dr. Stewart to its portfolio of gene expression tools,” says Dr. Lassner. “ We look forward to using those tools to improve animal production and improve the protein content of food crops.”
Dr. Stewart is quick to praise UTRF’s efforts in marketing his promoter technology to potential licensees. He is especially impressed by the staff’s dedication, exemplified by Maha Krishnamurthy, Ph.D., Assistant Vice President of Licensing at UTRF, who has invested time in learning about the bioenergy and agricultural markets (even taking one of Dr. Stewart’s plant biotechnology courses) to better understand their needs and how the University’s inventions can help meet them.
“Dr. Stewart’s promoters have demonstrated great potential in the field of genetic engineering,” says Dr. Krishnamurthy. “I look forward to seeing how Amfora will use this technology to create more nutritious and sustainable crops in the future.”
Currently, this promoter technology is being used to enhance resistance to insects and herbicides; however, Dr. Stewart envisions extending its application to traits that can have more significant impacts on plant health and growth, such as improving photosynthesis and increasing crop yields, as well as creating synthetic promoters that are designed specifically to drive expression for a desired trait.