Experimental conditions affecting ribonucleic acid polymerase in isolated @entity35 liver nuclei. Effect of nucleoside triphosphate concentration, temperature, XXXX and heparin.

@entity1025 @entity4859 @entity3281 @entity377 @entity35 @entity860
1. The conditions affecting the activity of RNA polymerase in isolated @entity35 liver nuclei were studied with @entity1025 or @entity3281 as activating ions. 2. The enzyme assayed with @entity1025 and at low ionic strength is saturated by a lower concentration of @entity377 substrates than if assayed with @entity3281 at low ionic strength or with either ion at high ionic strength. 3. At low and at high ionic strength the incorporation of @entity860 is affected in a similar way by variations in the temperature of incubation. Preincubation at 37 degrees impairs the @entity860 incorporation. 4. Heparin stimulates the RNA polymerase activity in the presence of @entity3281 . 5. Both @entity4859 and heparin ;restart' the reaction if added after 15min., the effect being more marked with @entity4859 than with heparin, and also more marked in the presence of @entity3281 than of @entity1025 . 6. alpha-Amanitin abolishes the effect of @entity4859 and of heparin.
