Programming DNA origami assembly for shape-resolved nanomechanical imaging labels

Nat Protoc. 2018 Jul;13(7):1569-1585. doi: 10.1038/s41596-018-0004-y.

Abstract

Atomic force microscopy (AFM)-based nanomechanical imaging provides a high-resolution approach for imaging biomolecules with nanometer resolution. Nevertheless, the lack of appropriate nanomechanical labels poses a limit to biological applications. Here, we describe how to generate a set of shape-resolved nanomechanical labels by exploiting self-assembled DNA origami technology. By designing 'mediator' strands that can hybridize with both the origami shapes and the target DNA, these origami shape IDs can be used to site-specifically label genomic DNA with high efficiency and high throughput. When DNA origami shape IDs are used to label target sequences containing two single-nucleotide polymorphisms (SNPs), this approach is capable of differentiating adjacent labeling sites separated by only 30 nucleobases (~10 nm) under AFM imaging. This resolution is a threefold improvement of that which can be obtained with imaging-based genotyping using super-resolution imaging. We further demonstrate how to use origami shape IDs for high-resolution genotyping of SNPs in disease-associated genes in patients. The entire protocol takes ~2 d to complete.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • DNA / chemistry
  • DNA / genetics*
  • DNA Probes / chemistry
  • DNA Probes / genetics*
  • Genotyping Techniques / methods*
  • Microscopy, Atomic Force / methods*
  • Nucleic Acid Hybridization
  • Staining and Labeling / methods*

Substances

  • DNA Probes
  • DNA