Enzymatic RNA synthesis with deoxynucleoside 5'‐O‐(1‐thiotriphosphates)

Abstract
We have investigated the incorporation of 2'‐deoxynucleoside‐5'‐O‐(1‐thiotriphosphates) into RNA transcripts using T7 RNA polymerase. With the exception of [α‐S]dGTP, we obtained full‐length transcripts of pre‐tRNAphe and pre‐tRNAtyr using an appropriate mixture of 2'‐deoxynucleoside 5'‐O‐(1‐thiotriphosphate) and the corresponding normal nucleoside triphosphate. The yields of the transcripts were comparable to those obtained with unmodified NTPs. Both substrates, [α‐S]dTTP and [α‐S]dATP, were inserted specifically. However, [α‐S]dCTP was excluded at specific sites. We could not obtain transcripts using the deoxyguanosine derivative.