Synthesis and properties of RNAs that contain a PNA-RNA dimer.

A practical synthesis of a peptide nucleic acid unit combined with an RNA nucleoside (PNA-RNA dimer) is reported. The dimer unit was placed within an RNA oligonucleotide via phosphoramidite chemistry and melting temperature data indicate destabilization relative to a native RNA duplex. Circular dichroism indicates that the overall shape of the duplex remains intact. This PNA-RNA dimer unit will permit future investigations within RNA-based systems, such as RNA interference.