Abstract
The genes coding for ribosomal RNa in plasmodia of Physarum polycephalum are arranged palindromically on extrachromosomal rDNA molecules of 61 kb (kilobasepairs). Incubation of mildly extracted rDNA with the 125I Bolton-Hunter reagent results in incorporation of label not removed by SDS, CsCl, or various organic solvents. Labeled protein is preferentially associated with terminal rDNA restriction fragments, as detected after gel electrophoresis of the DNA. Antibody reaction with dinitrophenylated protein-rDNA complexes allows visualization of protein located from 1 to 2 kb from the termini, in a region containing multiple inverted repeat sequences and single-strand gaps. DNase I treatment of either rDNA or rDNA termini releases primarily two labeled protein bands of 5,000 and 13,000 daltons as well as less prominent bands of higher molecular weight. We discuss mechanisms for involvement of terminal protein in replication of 3' ends and chromosomal integration of the rDNA.
Full Text
The Full Text of this article is available as a PDF (1.0 MB).
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Been M. D., Champoux J. J. Breakage of single-stranded DNA by rat liver nicking-closing enzyme with the formation of a DNA-enzyme complex. Nucleic Acids Res. 1980 Dec 20;8(24):6129–6142. doi: 10.1093/nar/8.24.6129. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Blackburn E. H., Chiou S. S. Non-nucleosomal packaging of a tandemly repeated DNA sequence at termini of extrachromosomal DNA coding for rRNA in Tetrahymena. Proc Natl Acad Sci U S A. 1981 Apr;78(4):2263–2267. doi: 10.1073/pnas.78.4.2263. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Braun R., Evans T. E. Replication of nuclear satellite and mitochondrial DNA in the mitotic cycle of Physarum. Biochim Biophys Acta. 1969 Jun 17;182(2):511–522. doi: 10.1016/0005-2787(69)90203-2. [DOI] [PubMed] [Google Scholar]
- Campbell G. R., Littau V. C., Melera P. W., Allfrey V. G., Johnson E. M. Unique sequence arrangement of ribosomal genes in the palindromic rDNA molecule of Physarum polycephalum. Nucleic Acids Res. 1979 Apr;6(4):1433–1447. doi: 10.1093/nar/6.4.1433. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Challberg M. D., Desiderio S. V., Kelly T. J., Jr Adenovirus DNA replication in vitro: characterization of a protein covalently linked to nascent DNA strands. Proc Natl Acad Sci U S A. 1980 Sep;77(9):5105–5109. doi: 10.1073/pnas.77.9.5105. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Goldbach R. W., Bollen-de Boer J. E., van Bruggen E. F., Borst P. Replication of the linear mitochondrial DNA of Tetrahymena pyriformis. Biochim Biophys Acta. 1979 May 24;562(3):400–417. doi: 10.1016/0005-2787(79)90104-7. [DOI] [PubMed] [Google Scholar]
- Hall L., Braun R. The organisation of genes for transfer RNA and ribosomal RNA in amoebae and plasmodia of Physarum polycephalum. Eur J Biochem. 1977 Jun 1;76(1):165–174. doi: 10.1111/j.1432-1033.1977.tb11582.x. [DOI] [PubMed] [Google Scholar]
- Johnson E. M. A family of inverted repeat sequences and specific single-strand gaps at the termini of the Physarum rDNA palindrome. Cell. 1980 Dec;22(3):875–886. doi: 10.1016/0092-8674(80)90564-4. [DOI] [PubMed] [Google Scholar]
- Mohberg J., Babcock K. L., Haugli F. B., Rusch H. P. Nuclear DNA content and chromosome numbers in the myxomycete Physarum polycephalum. Dev Biol. 1973 Oct;34(2):228–245. doi: 10.1016/0012-1606(73)90352-7. [DOI] [PubMed] [Google Scholar]
- Molgaard H. V., Matthews H. R., Bradbury E. M. Organisation of genes for ribosomal RNA in Physarum polycephalum. Eur J Biochem. 1976 Sep 15;68(2):541–549. doi: 10.1111/j.1432-1033.1976.tb10842.x. [DOI] [PubMed] [Google Scholar]
- Rekosh D. M., Russell W. C., Bellet A. J., Robinson A. J. Identification of a protein linked to the ends of adenovirus DNA. Cell. 1977 Jun;11(2):283–295. doi: 10.1016/0092-8674(77)90045-9. [DOI] [PubMed] [Google Scholar]
- Vogt V. M., Braun R. Structure of ribosomal DNA in Physarum polycephalum. J Mol Biol. 1976 Sep 25;106(3):567–587. doi: 10.1016/0022-2836(76)90252-7. [DOI] [PubMed] [Google Scholar]
- Vogt V. M., Braun R. The replication of ribosomal DNA in Physarum polycephalum. Eur J Biochem. 1977 Nov 1;80(2):557–566. doi: 10.1111/j.1432-1033.1977.tb11912.x. [DOI] [PubMed] [Google Scholar]
- Wu M., Davidson N. An electron microscopic method for the mapping of proteins attached to nucleic acids. Nucleic Acids Res. 1978 Aug;5(8):2825–2846. doi: 10.1093/nar/5.8.2825. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Wu M., Hyman R. W., Davidson N. Electron microscopic mapping of proteins bound to herpes simplex virus DNA. Nucleic Acids Res. 1979 Aug 10;6(11):3427–3441. doi: 10.1093/nar/6.11.3427. [DOI] [PMC free article] [PubMed] [Google Scholar]