Clemson Researcher Developing Genetically-Enhanced Perennial Grasses as Potential Fuel Source
The U.S. Department of Agriculture (USDA) National Institute of Food and Agriculture has awarded Hong Luo, a Clemson University College of Science Professor with the Department of Genetics and Biochemistry, a $500,000 grant to develop genetically enhanced and more resilient turfgrass and switchgrass.
These perennial plants, which constitute a multibillion-dollar sector of the U.S. agricultural economy, are found nationwide on athletic fields, cemeteries, golf courses, and parks. While turf and switchgrass can grow in harsh soil conditions using fewer resources than corn, these plants require large amounts of water, making them sensitive to extreme heat and drought. With Luo’s genetic enhancements, perennial grasses could become a favorable biofuel source producing high ethanol yields.
One obstacle faced with genetic-engineering is preventing the spillover of lab-engineered genes into the non-modified grasses or weeds growing in nearby fields, which could have unforeseeable effects on the environment. Luo’s approach to trans-gene containment is to merge two site-specific DNA recombination systems using completely sterile induction mechanisms.
The first line will consist of three active genes for Cre recombinase, hygromycin resistance (hyg) and endonuclease Cas9, and an inactive RNAi expression cassette for a flowering control gene, FLO/LFY homolog. The second line will contain an active herbicide resistance gene bar, recombinase gene phiC31 and FLO/LFY homolog gene guide RNA (sgRNA), and an inactive stress-regulating rice SUMO E3 ligase gene, OsSIZ1. When the two lines are cross-pollinated in the lab, specific genes will be activated and others removed, forming a more stress-resistant line.
The genetically enhanced plants will be completely sterile and produce no pollen or seeds, making it impossible for the modified genes to spread. By the end of the four-year project, Luo expects the new transgenic line to be ready for testing, with stringent USDA field tests and commercialization following.
Before joining the Clemson faculty, Luo led the development of the first genetically altered, environmentally safe, male-sterile and herbicide-resistant turfgrass while serving as the director of research at HybriGene, Inc. He also assisted in creating a new approach for hybrid crop production using site-specific DNA recombination systems.
To learn more about Hong Luo and his research in transgenic plants genomics, click here.