PT - JOURNAL ARTICLE AU - Filip Bošković AU - Ulrich Felix Keyser TI - Nanopore microscope identifies RNA isoforms with structural colors AID - 10.1101/2021.10.16.464631 DP - 2021 Jan 01 TA - bioRxiv PG - 2021.10.16.464631 4099 - http://biorxiv.org/content/early/2021/10/16/2021.10.16.464631.short 4100 - http://biorxiv.org/content/early/2021/10/16/2021.10.16.464631.full AB - Identifying RNA transcript isoforms requires intricate protocols that suffer from various enzymatic biases. Here we design three-dimensional molecular constructs that enable identification of transcript isoforms at the single-molecule level using solid-state nanopore microscopy. We refold target RNA into RNA identifiers (IDs) with designed sets of complementary DNA strands. Each reshaped molecule carries a unique sequence of structural (pseudo)colors. Structural colors consist of DNA structures, protein labels, native RNA structures, or a combination of all three. The sequence of structural colors of RNA IDs enables simultaneous identification and relative quantification of multiple RNA targets without prior amplification. Our Amplification-free RNA TargEt Multiplex Isoform Sensing (ARTEMIS) reveals structural arrangements in native transcripts in agreement with published variants. ARTEMIS discriminates circular and linear transcript isoforms in a one step, enzyme-free reaction in a complex human transcriptome using single-molecule readout.One sentence summary Here we show enzyme-free identification and relative quantification of RNA isoforms using a nanopore microscope and structural colors.Competing Interest StatementF.B. and U.F.K. have filed a priority patent application for the ARTEMIS method