Mitochondrial RNA polymerase activity from rat liver has previously been demonstrated in intact organelles. This activity has now been solubilized, partially purified, and shown to be a true polymerase, free of nuclease. The enzyme is derived from mitochondria and is not from contaminating bacteria or nuclear components. The enzyme is distinguished from its nuclear counterparts by its behavior ...

The injection of oestradiol to the prepuberal or castrated rat results, 2-3 hr later, in a large increase in RNA biosynthesis [l] and in an increased ability of uterine nuclei to incorporate nucleoside triphosphates into RNA [2]. Various reports have established that oestrogen-stimulated RNA is largely of ribosomal nature [3,4] . Recently, two different classes of DNAdependent RNA polymerases h...

tistical results in medical journals have emphasized confidence intervals (CIs) as an adjunct to, or even a replacement for, statistical tests and p values. Because of the intimate links between the 2 concepts, authors now use statements like “the 95% CI overlaps 0” where they would formerly have stated “the difference is not statistically significant at the 5% level.” Although this interchange...

An effective method for the isolation of nucleoli from auxin-treated soybean (Glycine max, var. Wayne) hypocotyl was developed by polytron homogenization and sucrose gradient centrifugation. The nucleoli expressed only the alpha-amanitin-insensitive RNA synthetic activity. This activity chromatographed as RNA polymerase I on DEAE-cellulose. It appears that the plant nucleolus, like the animal n...

RNA synthesis in isolated brain nuclei was analyzed 2.5 hr after the intravenous administration of d-lysergic acid diethylamide (LSD) to young rabbits. The drug stimulated transcription by 54% in brain stem nuclei and by 13% in cerebral hemisphere nuclei expressed over saline controls. Both nucleoplasmic and nucleolar RNA synthesis were increased. The main activity in the isolated nuclei assay ...

Methyl mercury has previously been shown to inhibit DNA and RNA synthesis in intact HeLa cells (Gruenwedel, D. W., and Cruikshank, M. K. (1979) Biochem. Pharmacol. 28, 651-655). Its effect on nucleic acid synthesis in vitro in isolated nuclei has now been investigated. DNA synthesis in nuclei was inhibited by methyl mercury; 50% inhibition was obtained with a concentration of 8 microM, compared...