Abstract

The α-hemolysin nanopore has been studied for applications in DNA sequencing, various single-molecule detections, biomolecular interactions, and biochips. The detection of single molecules in a clinical setting could dramatically improve cancer detection and diagnosis as well as develop personalized medicine practices for patients. This brief review shortly presents the current solid state and protein nanopore platforms and their applications like biosensing and sequencing. We then elaborate on various epigenetic detections (like microRNA, G-quadruplex, DNA damages, DNA modifications) with the most widely used alpha-hemolysin pore from a biomedical diagnosis perspective. In these detections, a nanopore electrical current signature was generated by the interaction of a target with the pore. The signature often was evidenced by the difference in the event duration, current level, or both of them. An ideal signature would provide obvious differences in the nanopore signals between the target and the background molecules. The development of cancer biomarker detection techniques and nanopore devices have the potential to advance clinical research and resolve health problems. However, several challenges arise in applying nanopore devices to clinical studies, including super low physiological concentrations of biomarkers resulting in low sensitivity, complex biological sample contents resulting in false signals, and fast translocating speed through the pore resulting in poor detections. These issues and possible solutions are discussed.

Highlights

  • Epigenetics referred to the molecular pathways modulating the expression of a genotype into a particular phenotype, but the meaning of the term has gradually narrowed over the decades [1]

  • Epigenetics refers to the changes to the genome that do not involve a change in the nucleotide sequence

  • G-quadruplex plays an important role in epigenetics and regulation processes, as well as having the potential to serve as the drug target of G-quadruplex binding proteins [69,70,71,72,73]

Read more

Summary

Epigenetics and its detections

Epigenetics referred to the molecular pathways modulating the expression of a genotype into a particular phenotype, but the meaning of the term has gradually narrowed over the decades [1]. Unlike genetics studies based on alterations to the DNA sequence (the genotype), the epigenetics refer to the changes in gene expression or cellular phenotype which have other causes. Examples of mechanisms that produce such changes are DNA methylation, loss of imprinting and histone modification, each of which affects how genes are expressed but without altering the underlying DNA sequence. Detection of epigenetic alterations as biomarkers for cancer detection, diagnosis and prognosis have been studied extensively and were advanced rapidly [5,6,7]

Nanopore
Nanopore applications
Developing probes for multiplex microRNA detection
G-quadruplex Folding and Detections
Folding and unfolding of G-quadruplex subtypes in a confined space
Detection of DNA Damages
Detection of guanine oxidation in the human telomere repeat sequence
Detection of abasic site in the β-barrel site of the nanopore
Cytosine Modifications Detections
Methylation detection by designing a mercury interstrand lock
Nanopore Devices
Findings
Conclusion
Full Text
Published version (Free)

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call