Probing secondary structures of spin-labeled RNA by pulsed EPR spectroscopy.

Tempo, TEMPO! Spin-labeled RNAs are readily prepared by postsynthetic modification of RNA. This approach provides access to paramagnetic oligonucleotides with position-specific probes in cytidine, adenosine, and guanosine nucleobases (CT, AT, GT, respectively). In this way alternative RNA secondary structures can be investigated by distance measurements using pulsed EPR spectroscopy