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Updated: Jul 8, 2026

DNA-Tethered RNA Polymerase for Programmable In vitro Transcription and Molecular Computation
Published on: December 29, 2021
[DNA-dependent RNA polymerase activity of isolated zooflagellates (Crithidia oncopelti) nucleoli]
Abstract:
A fraction of nucleoli is isolated from zooflagellates (Crithidia oncopelti) nuclei, its DNA-dependent RNA polymerase activity is studied at different temperature, ionic strength and Mg2+, Mn2+ and antibiotic concentrations. The effect of some factors and alpha-amantine on RNA polymerase activity of exonucleolar chromatin was studied as a control. A comparison of heat denaturation of nucleoli and chromatin RNA polymerase activities within the temperature range 30--55 degrees C has revealed a higher thermosensitivity of nucleoli RNA polymerase. Substitution of Mg2+ with equivalent amount of Mn2+ results in a considerable decrease of rRNA synthesis in nucleoli. Nucleoli RNA polymerase activity in the presence of Mg2+ is sensitive to the elevation of ionic strength from 0.12 to 1.30 u; chromatin RNA polymerase activity in the presence of Mn2+ is maximal at high ionic strength (1.30 mu). alpha-Amantine and cycloheximide at high concentrations (10 and 200 mkg/ml) practically do not affect RNA polymerase activity of nucleoli. Nucleoli RNA polymerase of zooflagellates (Crithidia oncopelti) is similar to the A-form of the enzyme in higher eukaryotes.
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