Abstract
Slater, R. J. and Bryant, J. A. 1987. RNA polymerase activity during breakage of seed dormancy by low temperature treatment of fruits of Acer platanoides (Norway maple).—J. exp. Bot. 38:1026–1032. Endogenous RNA polymerase activity has been characterized in nuclei isolated from embryo axes of Acer platanoides. Optimal activity was recorded at 4·0 mol m−3 MgCl2 and 50 mol m−3 (NH4)2SO4 and total activity could be inhibited by up to 30% by α-amanitin. Stratification of fruits leads to a stimulation of RNA polymerase activity. A minimum of 3 d cold treatment is required with at least 3-fold stimulation recorded after 10 d at 4°C. The increased enzyme activity is resistant to α-amanitin suggesting an effect on RNA polymerase I.