Direct Detection of Conserved Viral Sequences and Other Nucleic Acid Motifs with Solid-State Nanopores

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Sethi, Komal, Gabrielle P. Dailey, Osama K. Zahid, Ethan W. Taylor, Jan A. Ruzicka, and Adam R. Hall. "Direct Detection of Conserved Viral Sequences and Other Nucleic Acid Motifs with Solid-State Nanopores." ACS nano 15, no. 5 (2021): 8474-8483.

The rapid and reliable recognition of nucleic acid sequences is essential to a broad range of fields including genotyping, gene expression analysis, and pathogen screening. For viral detection in particular, the capability is critical for optimal therapeutic response and preventing disease transmission. Here, we report an approach for detecting identifying sequence motifs within genome-scale single-strand DNA and RNA based on solid-state nanopores. By designing DNA oligonucleotide probes with complementarity to target sequences within a target genome, we establish a protocol to yield affinity-tagged duplex molecules the same length as the probe only if the target is present. The product can subsequently be bound to a protein chaperone and analyzed quantitatively with a selective solid-state nanopore assay. We first use a model DNA genome (M13mp18) to validate the approach, showing the successful isolation and detection of multiple target sequences simultaneously. We then demonstrate the protocol for the detection of RNA viruses by identifying and targeting a highly conserved sequence within human immunodeficiency virus (HIV-1B).

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