A micropatterned substrate for on-surface enzymatic labelling of linearized long DNA molecules

Sci Rep. 2019 Oct 21;9(1):15059. doi: 10.1038/s41598-019-51507-z.

Abstract

Optical mapping of linearized DNA molecules is a promising new technology for sequence assembly and scaffolding, large structural variant detection, and diagnostics. This is currently achieved either using nanochannel confinement or by stretching single DNA molecules on a solid surface. While the first method necessitates DNA labelling before linearization, the latter allows for modification post-linearization, thereby affording increased process flexibility. Each method is constrained by various physical and chemical limitations. One of the most common techniques for linearization of DNA uses a hydrophobic surface and a receding meniscus, termed molecular combing. Here, we report the development of a microfabricated surface that can not only comb the DNA molecules efficiently but also provides for sequence-specific enzymatic fluorescent DNA labelling. By modifying a glass surface with two contrasting functionalities, such that DNA binds selectively to one of the two regions, we can control DNA extension, which is known to be critical for sequence-recognition by an enzyme. Moreover, the surface modification provides enzymatic access to the DNA backbone, as well as minimizing non-specific fluorescent dye adsorption. These enhancements make the designed surface suitable for large-scale and high-resolution single DNA molecule studies.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • DNA / metabolism*
  • Fluorescence
  • Humans
  • Microtechnology*
  • Molecular Weight
  • Polyethylene Glycols / chemistry
  • Staining and Labeling*
  • Substrate Specificity
  • Surface Properties

Substances

  • Polyethylene Glycols
  • DNA