Nagamine Y, Mizuno D, Natori S
Biochim Biophys Acta. 1978 Jul 24;519(2):440-6. doi: 10.1016/0005-2787(78)90097-7.
The effects of magnesium and manganese in the initiation and elongation steps of the RNA polymerase I reaction in RNA synthesis were studied. For RNA chain initiation manganese was found to be a better effector than magnesium. For RNA chain elongation either manganese or magnesium acted as an effector, but a high concentration of manganese was inhibitory.