Interferon, double-stranded RNA and RNA degradation. Fractionation of the endonucleaseINT system into two macromolecular components; role of a small molecule in nuclease activation

We reported earlier that a) the incubation of an extract from interferon-treated Ehrlich ascites tumor cells with double-straded RNA and ATP results in the activation of an endonuclease and b) after the activation the double-stranded RNA and ATP can be degraded without impairing the activity of the endonuclease. We report now the separation and partial purification of two macromolecular components (DE1_INT and DE2_INT) involved in the process. Upon incubation with double-stranded RNA and ATP component DE1_INT generates a heat-stable product of low molecular weight (designated as nuclease activator). On incubation with the nuclease activator a latent nuclease in component DE2_INT is activated.