Transient and Switchable (Triethylsilyl)ethynyl Protection of DNA against Cleavage by Restriction Endonucleases

Abstract

Restricted access to DNA: (Triethylsilyl)ethynyl-modified 7-deaza-dATP is readily incorporated into DNA by primer extension or polymerase chain reaction using KOD XL polymerase. The silylethynyl- protected DNA resists the cleavage by restriction endonucleases (REs), such as RsaI (see scheme), but after it is treated with NH3, the resulting deprotected DNA is fully cleavable by the REs.