Development of Photoswitchable Nucleotides to Control RNA Biochemistry

With this award, the Chemistry of Life Processes Program in the Chemistry Division is funding Drs. Jia Sheng and Ting Wang from University at Albany, State University of New York to develop nucleic acid building blocks that are responsive to light. The structures and functions of RNAs synthesized with these nucleic acids are studied to determine their abilities to serve as photoswitchable regulators of gene expression or therapeutics. In this way, when and where the functions of these light responsive RNAs are turned on or off can be controlled in ways that are noninvasive and, thus, safe to cells. The students participating in this research receive broad training in synthetic organic chemistry, physical chemistry, analytical chemistry, and nucleic acid chemistry, as well as skills in macromolecule X-ray crystallography and computational modeling of biological molecules. Such training provides highly motivated graduate and undergraduate students with skills required to enter careers in the life sciences and STEM fields in general. In addition, a set of “Preparation of Organic Chemistry” orientation sessions are established to help entering undergraduate students navigate the rigors of college-level organic chemistry. Finally, this project is integrated into an outreach science education program that provides curiosity driven hands-on experimental experiences to K-12 students. In this research project, photoswitchable nucleotide building blocks are synthesized and incorporated into RNA oligonucleotides to control their structures and functions. More specifically, a series of azobenzene-based nucleosides are designed to change conformations in response to different light wavelengths. RNA strands synthesized with these light responsive nucleotides are characterized for their ability to form stable and specific base pairs and the ability of light to drive their conformations and functions, including, RNA aptamer and ribozyme activities, and RNA-enzyme recognitions such as reverse transcription and CRISPR-Cas13-mediated RNA cleavage for genetic engineering. These photo-responsive nucleotides could also be applied to other classes of important RNAs such as microRNA, small interfering RNAs (siRNA), peptide-nucleic acids (PNA), methylene-bridged locked nucleic acids (LNA) and other non-coding RNAs for applications in biomedical research. Overall, this work advances our understanding and applications of fundamental RNA biology by creating new chemical biology toolset, which can be applied to more advanced cellular and animal studies and to develop new therapeutics and biomaterials. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.