Intellectual Merit. All organisms, from viruses to man, must synthesize proteins from their genomes by the process of protein synthesis (translation). Plant viruses are especially intriguing, as they must compete with their host cells for limited translation factors without killing the cell. Research on plant viruses has revealed that the end of the RNA genome most distal to where translation begins (the 3' end) is a critical region for attracting components of translation to the genome, leading to substantially enhanced translation. The 3' region of one virus with an RNA genome, Pea enation mosaic virus, was recently found to contain a translational enhancer that attracts ribosomes, the central protein synthesizing machines, and may function by helping ribosomes recycle following genome translation. In addition, this translational enhancer also participates in a long-distance joining with another element near the other end (the 5' end) of the virus. This project will examine how this translational enhancer interacts with ribosomes and whether ribosomes can "bridge" the ends of the viral genome by interacting simultaneously with both 3' and 5' RNA elements. Since viral genomes cannot be replicated and translated at the same time, this research will also investigate how the virus switches between these incompatible activities. Finally, the research will explore the possibility that the host plant's genome contains similar ribosome-binding elements that enhance translation of host RNAs. Developing new paradigms for how the 3' region participates in translation will prompt other investigators to correctly examine their genes or viruses for 3' translational enhancers, which will be transformative in the translation field. By understanding how these translational enhancers function, it should be possible to include them when designing new ways to produce higher levels of products in plants for improvement of agricultural traits.
Broader Impacts. This research will be conducted by graduate and postdoctoral researchers, who will learn state-of-the art techniques and model-building to enhance their development as scientists. Undergraduate researchers will also participate in all aspects of this project, learning about the excitement of scientific discoveries. Enthusiasm for research-based discovery will continue to be conveyed weekly to Advanced Placement high school students and teachers at DuVal High School (98% minority) in Prince George's County, Maryland, with several students already benefiting by being accepted at top colleges/universities and majoring in STEM subjects. The principal investigator will also continue to effectively represent science and scientists to the public, most recently as a consultant for a Discovery TV Series and participation in activities such as the Saturday morning science program at the University of Toledo. Specific examples from this research will also be used to excite and enhance the education experience of students in their first year as science majors at the University of Maryland through an introductory biology course taught by the principal investigator.