miR-ID: A novel, circularization-based platform for detection of microRNAs

Side-by-side comparison of circularization of 2′-OH miRNA by ligases Rnl1 and CLII. Synthetic let-7b miRNA having 5′-p and 2′-OH/3′-OH ends was used in this example. Standard curves were generated for a dilution series from 200 pM to 20 aM let-7b for miR-ID assays in which either T4 RNA ligase 1 (Rnl1) or CircLigase II (CLII) was used in the circularization step, followed by the usual RTC and qPCR steps.