DNA-synthesis on giant nuclear RNA by AMV DNA polymerase.

The reverse transcription of pre-mRNA isolated from rat liver or mouse Ehrlich ascites carcinoma cells with the aid of hot phenol fractionation technique is described. Pre-mRNA isolated at 85 degrees C is a more active template than the 65 degree C fraction. The addition of oligo(dT) as a primer strongly stimulated the template activity of the 65 degree C fraction. The size of product corresponds to a sedimentation value of 7 S as measured in alkaline sucrose gradient and is essentially less than the size of template.