nl9b03184_si_001.pdf (1.32 MB)
Monitoring G‑Quadruplex Formation with DNA Carriers and Solid-State Nanopores
journal contribution
posted on 2019-10-10, 18:07 authored by Filip Bošković, Jinbo Zhu, Kaikai Chen, Ulrich F. KeyserG-quadruplexes (Gqs)
are guanine-rich DNA structures formed by
single-stranded DNA. They are of paramount significance to gene expression
regulation, but also drug targets for cancer and human viruses. Current
ensemble and single-molecule methods require fluorescent labels, which
can affect Gq folding kinetics. Here we introduce, a single-molecule
Gq nanopore assay (smGNA) to detect Gqs and kinetics of Gq formation.
We use ∼5 nm solid-state nanopores to detect various Gq structural
variants attached to designed DNA carriers. Gqs can be identified
by localizing their positions along designed DNA carriers, establishing
smGNA as a tool for Gq mapping. In addition, smGNA allows for discrimination
of (un)folded Gq structures, provides insights into single-molecule
kinetics of Gq folding, and probes quadruplex-to-duplex structural
transitions. smGNA can elucidate the formation of Gqs at the single-molecule
level without labeling and has potential implications on the study
of these structures both in single-stranded DNA and in genomic samples.