Degradation of the Ribosomal Genes by DNAse I in Physarum polycephalum
Open Access
- 1 October 1978
- journal article
- research article
- Published by Wiley in European Journal of Biochemistry
- Vol. 90 (2), 391-395
- https://doi.org/10.1111/j.1432-1033.1978.tb12616.x
Abstract
Treatment of nuclei from Physarum polycephalum with DNAse I leads to DNA fragments with a regular pattern of multiples of 10 nucleotides, when analyzed on gels under denaturing conditions as has been shown for other eukaryotes. Reports from Weintraub and Axel lead to the conclusion, that active genes are preferentially digested by DNAse I. When Physarum chromatin is degraded by DNAse I, the ribosomal genes are no longer available for hybridization with 19-S and 26-S rRNA and are thus preferentially destroyed. Degradation of chromatin from nuclei in mitosis, where no rRNA is synthesized and from nuclei in late G2 phase, where rRNA synthesis is maximal, leads to the same proportion of the ribosomal sequences being lost for hybridization. Therefore the preferential degradation of the ribosomal genes in Physarum by DNAse I probably does not reflect the actual momentary activity of these genes. This suggests that DNAse I treatment may distinguish between active chromatin and very strongly repressed chromatin.This publication has 29 references indexed in Scilit:
- The Replication of Ribosomal DNA in Physarum polycephalumEuropean Journal of Biochemistry, 1977
- An altered subunit configuration associated with the actively transcribed DNA of integrated adenovirus genesCell, 1977
- Pancreatic DNAase cleavage sites in nucleiCell, 1977
- Chromatin structure as probed by nucleases and proteases: Evidence for the central role of hitones H3 and H4Cell, 1976
- Comparative organization of active transcription units in Oncopeltus fasciatusCell, 1976
- Structure of ribosomal DNA in Physarum polycephalumJournal of Molecular Biology, 1976
- Synthesis of Ribosomal RNA during the Mitotic Cycle in the Slime Mould Physarum polycephalumEuropean Journal of Biochemistry, 1976
- Structural repeating units in chromatinExperimental Cell Research, 1976
- Chromatin sub-structure. The digestion of chromatin DNA at regularly spaced sites by a nuclear deoxyribonucleaseBiochemical and Biophysical Research Communications, 1973
- Isolation and DNA content of nuclei of Physarum polycephalumExperimental Cell Research, 1971