CAREER: Programming digital bits with DNA for barcoded nanoscale imaging applications

University Of California-San Francisco, San Francisco CA

Investigators

Abstract

Nontechnical explanation: Biomolecules are the tiny molecular building blocks out of which all living organisms are made. Understanding the structure and function of biomolecules is critical for advancement of our understanding of how life works, as well as emerging engineering disciplines that seek to repurpose biomolecules for technology development. Electron cryo-microscopy (cryo-EM) enables researchers to visualize the structure of biomolecules. One technical limitation of the technique is that biomolecules must be imaged one at a time because they are too small to tell apart when mixed together. It would be a significant advance if it were possible to attach "barcodes" to biomolecules so they could be imaged simultaneously and uniquely identified during data analysis. The goal of this project is to create and optimize such barcodes using DNA as a nano-scale programmable building material. If successful, the proposed approach should greatly increase the speed and impact of the cryo-EM technique. Technical description: Toward overcoming the throughput limitation of electron cryo-microscopy (cryo-EM), PI proposes to create DNA-based nanostructures that make use of modular, well-defined asymmetric features ("bits") that can be toggled between different states that enable sample multiplexing. The structural difference of toggling even a single bit is dramatic enough that different barcodes can be easily distinguished by EM, and sorted into distinct classes by standard image processing algorithms. PI proposes to validate this methodology by first performing structural studies of nanostructures bound to a protein that has already been imaged and described, and then extend this research to image and describe macromolecules that have not yet been visualized by other methods.