Tandem Oligonucleotide Synthesis (TOS) of (chemically modified) DNA and RNA using a commercially available cleavable linker. We show that the 2,2′-sulfonyldiethylene linker is effectively incorporated in DNA/RNA sequences, and efficiently cleaved during standard nucleic acid deprotection protocols. Moreover, we utilize our TOS approach to perform ligation experiments to incorporate N3′→P5′ phosphoramidate, and pyrophosphate linkages in DNA strands

Abstract

Tandem oligonucleotide synthesis (TOS) is an attractive strategy to increase automated oligonucleotide synthesis efficiency. TOS is accomplished via the introduction of an immolative linker within a single sequence composed of multiple oligonucleotide fragments. Here, we report the use of a commercially available building block, typically utilized for the chemical phosphorylation of DNA/RNA oligomers, to perform TOS. We show that the 2,2′-sulfonyldiethylene linker is efficiently self-immolated during the standard deprotection of DNA and RNA and presents itself as a generalizable methodology for nucleic acid TOS. Furthermore, we show the utility of this methodology by assembling a model siRNA construct, and showcase a template-directed ligation pathway to incorporate phosphoramidate or pyrophosphate linkages within DNA oligomers.

Saraya and O'Flaherty report the use of a commercially available building block, typically used for chemical phosphorylation, to perform Tandem Oligonucleotide Synthesis (TOS). The TOS strategy allows the facile preparation of multiple DNA/RNA oligomers separated by a cleavable linker. The immolation of these linkers occurs during the standard ammonium hydroxide deprotection. (designed by Tiffany A. Mills). More information can be found in the Research Article by J. S. Saraya, D. K. O'Flaherty.