A scintillation proximity assay for RNA detection

A homogeneous scintillation proximity assay (SPA) for detection of RNA tran scripts is described. H-3-labeled RNA transcripts are hybridized in solutio n to biotinylated oligodeoxynucleotides (ODNs), which are then bound by str eptavidin-coated, scintillant-embedded beads. Only bound H-3-labeled RNA tr anscripts are brought in close enough proximity to stimulate light emission from the beads, The results from this novel homogeneous assay correlated w ell with those obtained using the traditional filter-binding methods to mea sure RNA polymerase activity. The assay has been miniaturized to a 384-well format compatible with automated high-throughput screening. This SPA metho d has also been successfully used to probe RNA-accessible sites to hybridiz ation, and thus should provide a useful tool for selecting effective antise nse ODNs in antisense research. (C) 2001 Academic Press.