Solid-Phase Synthesis of RNA Analogs Containing Phosphorodithioate Linkages

Curr Protoc Nucleic Acid Chem. 2017 Sep 18:70:4.77.1-4.77.13. doi: 10.1002/cpnc.40.

Abstract

The oligoribonucleotide phosphorodithioate (PS2-RNA) modification uses two sulfur atoms to replace two non-bridging oxygen atoms at an internucleotide phosphorodiester backbone linkage. Like a natural phosphodiester RNA backbone linkage, a PS2-modified backbone linkage is achiral at phosphorus. PS2-RNAs are highly stable to nucleases and several in vitro assays have demonstrated their biological activity. For example, PS2-RNAs silenced mRNA in vitro and bound to protein targets in the form of PS2-aptamers (thioaptamers). Thus, the interest in and promise of PS2-RNAs has drawn attention to synthesizing, isolating, and characterizing these compounds. RNA-thiophosphoramidite monomers are commercially available from AM Biotechnologies and this unit describes an effective methodology for solid-phase synthesis, deprotection, and purification of RNAs having PS2 internucleotide linkages. © 2017 by John Wiley & Sons, Inc.

Keywords: PS2-RNA; phosphorodithioate oligoribonucleotide; solid-phase synthesis; sulfur-modified oligonucleotide; thiophosphoramidite.

MeSH terms

  • Oligonucleotides
  • Phosphates / chemistry*
  • RNA / chemical synthesis*
  • Solid-Phase Synthesis Techniques*

Substances

  • Oligonucleotides
  • Phosphates
  • RNA
  • phosphorodithioic acid