Inhibition of in vitro transcription by adenosine antibodies

Antibodies against adenosine markedly inhibited in vitro transcription in isolated BHK 21 nuclei in a dose-dependent manner. The inhibition was specific as it could be completely reversed by the addition of homologous hapten. Addition of RNA at low concentration reversed the inhibition, whereas excess DNA did not have any effect. Adenosine antibodies also inhibited in vitro transcription with calf thymus DNA and E. coli RNA polymerase. Antibodies that react with DNA but not with RNA such as anti-dpA, anti-dpC and anti-DNA failed to inhibit in vitro transcription in isolated nuclei as well as with calf thymus DNA and E. coli RNA polymerase. The results strongly indicate that the binding of adenosine antibodies to RNA is responsible for the inhibition of transcription.