Refine
Has Fulltext
- yes (133) (remove)
Is part of the Bibliography
- yes (133)
Year of publication
Document Type
- Journal article (107)
- Conference Proceeding (12)
- Book article / Book chapter (8)
- Review (5)
- Book (1)
Keywords
- Cytologie (13)
- Amphibian oocytes (3)
- Electron microscopy (3)
- electron microscopy (3)
- mitosis (3)
- Botanik (2)
- Chromatin structure (2)
- DNA (2)
- DNA antibodies (2)
- Lampbrush chromosomes (2)
- Nucleolus (2)
- nucleolus (2)
- transcription (2)
- Acetabularia (1)
- Actinomycin D (1)
- Anatomie (1)
- Aneuploidy (1)
- Chemical nature (1)
- Chromatin (1)
- Cross-bridges (1)
- DNA immunolocalization (1)
- Deutschland (1)
- Eukaryonten / Chromosom (1)
- Gefäßpflanzen (1)
- Golgi apparatus (1)
- Harold Garnet Callan (1)
- Hybridisierung <Biologie> (1)
- Membranes (1)
- Merogone experiments (1)
- Microtubules (1)
- Multipolar mitosis (1)
- Nuclear envelope (1)
- Nuclear pore complex (1)
- Nuclear pores (1)
- Nucleocytoplasmic exchange (1)
- Nucleocytoplasmic transport (1)
- Nucleolus-DNA (1)
- Oogenese (1)
- Polyspermy (1)
- Science history (1)
- Sea urchin development (1)
- Tetrahymena (1)
- Tierpsychologie (1)
- Transcription units (1)
- Tumor / Zellteilung (1)
- Verzeichnis (1)
- Xenopus oocytes (1)
- Zelldifferenzierung (1)
- Zellkern (1)
- amphibian oocytes (1)
- anti-RNA polymerase I antibodies (1)
- antibody (1)
- cAMP / cGMP / cytoskeleton / phosphorylation / protein kinase (1)
- camptothecin (1)
- chromatin (1)
- chromatin structure (1)
- evolution (1)
- fibrillar centers (1)
- gene activity (1)
- immunofluorescence (1)
- immunofluorescence microscopy (1)
- in situ hybridization (1)
- lampbrush chromosomes (1)
- monoclonal antibodies (1)
- monoclonal antibody (1)
- mycoplasma tests (1)
- nuclear envelope (1)
- nuclear organization (1)
- nucleologenesis (1)
- nucleolus organizer (1)
- nucleosomes (1)
- opoisomerase I (1)
- rDNA (1)
- rRNA genes (1)
- ribosomal RNA genes; electron microscopy; spread preparations (1)
- ribosomes (1)
- sperm (1)
- transcription units (1)
Institute
- Theodor-Boveri-Institut für Biowissenschaften (133) (remove)
RNA polymerase I preparations purified from a rat hepatoma contained DNA topoisomerase activity. The DNA topoisomerase associated with the polymerase had an Mr of 110000, required Mg2+ but not ATP, and was recognized by anti-topoisomerase I antibodies. When added to RNA polymerase I preparations containing topoisomerase activity, anti-topoisomerase I antibodies were able to inhibit the DNA relaxing activity of the preparation as well as RNA synthesis in vitro. RNA polymerase II prepared by analogous procedures did not contain topoisomerase activity and was not recognized by the antibodies. The topoisomerase I: polymerase I complex was reversibly dissociated by column chromatography on Sephacryl S200 in the presence of 0.25 M (NH4hS04. Topoisomerase I was immunolocalized in the transcriptionally active ribosomal gene complex containing RNA polymerase I in situ. These data indicate that topoisomerase I and RNA polymerase I are tightly complexed both in vivo and in vitro, and suggest a role for DNA topoisomerase I in the transcription of ribosomal genes.