Detection of 3-end RNA uridylation with a protein nanopore

Post-transcriptional modifications of the 3?-ends of RNA molecules have a profound impact on their stability and processing in the cell. Uridylation, the addition of uridines to 3?-ends, has recently been found to be an important regulatory signal to stabilize the tagged molecules or to direct them toward degradation. Simple and cost-effective methods for the detection of this post-transcriptional modification are not yet available. Here, we demonstrate the selective and transient binding of 3?-uridylated ssRNAs inside the ? barrel of the staphylococcal ?-hemolysin (?HL) nanopore and investigate the molecular basis of uridine recognition by the pore. We show the discrimination of 3?-oligouridine tails on the basis of their lengths and propose the ?HL nanopore as a useful sensor for this biologically relevant RNA modification. © 2013 American Chemical Society.