Isolation and characterization of DNA-dependent RNA polymerase I of Tetrahymena pyriformis.

  title={Isolation and characterization of DNA-dependent RNA polymerase I of Tetrahymena pyriformis.},
  author={Karl Mueller and Manfred Freiburg and G. Hoyer-Feige},
  journal={Journal of biochemistry},
  volume={98 5},
A procedure for the separation and purification of DNA-dependent RNA polymerases [EC] from macronuclei of Tetrahymena pyriformis is described. We have used it to isolate and characterize the class I enzyme. RNA polymerase I was identified by its resistance against alpha-amanitin and its location in nucleoli. The purified enzyme consists of at least 12 major subunits with approximate molecular weights of 180,000, 118,000, 37,500, 36,000, 29,000, 27,500, 20,000, 18,500, 15,600, 14,500, 13… 
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The isolation of gamones 3 and 4 of Euplotes octocarinatus.
Gamones 3 and 4 of the ciliate Euplotes octocarinatus were isolated and purified to chromatographic and electrophoretic homogeneity to induce cells of certain mating types to unite in pairs and exchange gametic nuclei.
Isolation of the Lembadion-Factor, a morphogenetically active signal, that induces Euplotes cells to change from their ovoid form into a larger lateral winged morph
The L-factor induces cells of the genus Euplotes to become less compact, which reduces their likelihood of becoming engulfed and develops extended wings and dorsal and ventral ridges and transforms within a few hours from its typical ovoid morph into an enlarged circular morph.
Predator‐induced morphological changes in Euplotes (Ciliata): Isolation of the inducing substance released from Stenostomum sphagnetorum (turbellaria)
The turbellarian Stenostomum sphagnetorum releases a morphogenetically active substance (S-factor) into the surrounding medium that transforms each Euplotes cell into an enlarged circular morph with extended lateral wings that make its engulfment by the predator more difficult.
Gamone Production in Large-Scale Cultures of Euplotes octocarinatus1
Frequent exchange of culture fluid proved more effective than aeration in obtaining high cell densities and reasonable doubling times in large-scale cultures of the freshwater ciliate Euplotes octocarinatus.