Hi-fidelity discrimination of isomiRs using G-quadruplex gatekeepers

Abstract

Core microRNA (miRNA) sequences exist as populations of variants called isomiRs made up of different lengths and nucleotide compositions. In particular, the short sequences of miRNA make single-base isomiR mismatches very difficult to be discriminated. Non-specific hybridizations often arise when DNA probe-miRNA target hybridization is the primary, or initial, mode of detection. These errors then become exacerbated through subsequent amplification steps. Here, we present the design of DNA probes modified with poly-guanine (PG) tracts that were induced to form G-quadruplexes (G4) for hi-fidelity discrimination of miRNA core target sequence from single-base mismatched isomiRs. We demonstrate t..