Intellectual Merit: The process of gene expression requires the synthesis of ribonucleic acid (RNA), which works as an intermediate (messenger RNA or mRNA) between genes and proteins. Interestingly, there are also many other classes of RNA which do not encode proteins, known as non-coding RNA. One of the most mysterious classes of non-coding RNA has been proposed to be a major factor contributing to the regulation of gene activity by controlling transcription (i.e., the rate of mRNA synthesis). The goal of this project is to resolve the molecular mechanisms used by non-coding RNA to regulate gene activity in a process known as transcriptional gene silencing. This research will use unique tools available with the model plant organism Arabidopsis thaliana to specifically eliminate a class of non-coding RNA. This manipulation, along with several other genetic, biochemical and genomic approaches, will be used to explain how non-coding RNA guides specific silencing factors to DNA. Experiments will also determine if the molecular mechanism of non-coding RNA function in transcriptional gene silencing is conserved throughout the genome, or if many independent gene-specific mechanisms exist. Overall, the project will provide a better understanding of how genes are regulated.
Broader impacts: The project integrates various levels of undergraduate teaching to inspire the next generation of scientists. It involves a revision of a large-enrollment undergraduate course in genetics, the design of a specialty course focused on the general area of this research, and direct involvement of undergraduate students in this research. Additionally, the project will benefit society by advancing our understanding of the basic mechanisms of life and by providing a foundation that could contribute to future improvement of crop plants.