Skip to main content
Proceedings of the National Academy of Sciences of the United States of America logoLink to Proceedings of the National Academy of Sciences of the United States of America
. 1981 Apr;78(4):2263–2267. doi: 10.1073/pnas.78.4.2263

Non-nucleosomal packaging of a tandemly repeated DNA sequence at termini of extrachromosomal DNA coding for rRNA in Tetrahymena.

E H Blackburn, S S Chiou
PMCID: PMC319325  PMID: 6941283

Abstract

A tandemly repeated DNA hexanucleotide sequence, 5'C-C-C-C-A-A3', that occurs at the termini of extrachromosomal DNA molecules coding for rRNA (rDNA) in Tetrahymena macronuclei was examined to determine whether it is packaged as nucleosomes. This repeated DNA sequence comprises the terminal few hundred base pairs at each end of the linear rDNA molecules. Digestion of macronuclei with micrococcal nuclease showed that this DNA sequence is protected from digestion but is left, following digestion, as a single but broad size class of DNA fragments several hundred base pairs long, under conditions in which bulk macronuclear DNA and rDNA were digested to fragments that were multiples of approximately 200 base pairs in length. The repeated C-C-C-C-A-A was found protected as fragments longer than the bulk macronuclear DNA digestion products at all times during digestion. Together with putative associated protein(s), this protected DNA was soluble after lysis of micrococcal nuclease-digested macronuclei at low salt concentrations but was insoluble in 0.075--0.2 M KCl, regardless of the extend of digestion. The size and solubility properties of the repeated C-C-C-C-A-A DNA nucleoprotein complex after micrococcal nuclease digestion of macronuclei are clearly distinguishable from those of nucleosomes, and it is inferred that this DNA sequence in macronuclei is packaged in chromatin by proteins other than histones.

Full text

PDF
2263

Images in this article

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Allis C. D., Glover C. V., Gorovsky M. A. Micronuclei of Tetrahymena contain two types of histone H3. Proc Natl Acad Sci U S A. 1979 Oct;76(10):4857–4861. doi: 10.1073/pnas.76.10.4857. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Blackburn E. H., Gall J. G. A tandemly repeated sequence at the termini of the extrachromosomal ribosomal RNA genes in Tetrahymena. J Mol Biol. 1978 Mar 25;120(1):33–53. doi: 10.1016/0022-2836(78)90294-2. [DOI] [PubMed] [Google Scholar]
  3. Blumenfeld M., Orf J. W., Sina B. J., Kreber R. A., Callahan M. A., Mullins J. I., Snyder L. A. Correlation between phosphorylated H1 histones and satellite DNAs in Drosophila virilis. Proc Natl Acad Sci U S A. 1978 Feb;75(2):866–870. doi: 10.1073/pnas.75.2.866. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Botchan M., Topp W., Sambrook J. The arrangement of simian virus 40 sequences in the DNA of transformed cells. Cell. 1976 Oct;9(2):269–287. doi: 10.1016/0092-8674(76)90118-5. [DOI] [PubMed] [Google Scholar]
  5. Cech T. R., Karrer K. M. Chromatin structure of the ribosomal RNA genes of Tetrahymena thermophila as analyzed by trimethylpsoralen crosslinking in vivo. J Mol Biol. 1980 Feb 5;136(4):395–416. doi: 10.1016/0022-2836(80)90397-6. [DOI] [PubMed] [Google Scholar]
  6. Engberg J., Andersson P., Leick V., Collins J. Free ribosomal DNA molecules from Tetrahymena pyriformis GL are giant palindromes. J Mol Biol. 1976 Jun 25;104(2):455–470. doi: 10.1016/0022-2836(76)90281-3. [DOI] [PubMed] [Google Scholar]
  7. Engelke D. R., Ng S. Y., Shastry B. S., Roeder R. G. Specific interaction of a purified transcription factor with an internal control region of 5S RNA genes. Cell. 1980 Mar;19(3):717–728. doi: 10.1016/s0092-8674(80)80048-1. [DOI] [PubMed] [Google Scholar]
  8. Felsenfeld G. Chromatin. Nature. 1978 Jan 12;271(5641):115–122. doi: 10.1038/271115a0. [DOI] [PubMed] [Google Scholar]
  9. Gall J. G. Free ribosomal RNA genes in the macronucleus of Tetrahymena. Proc Natl Acad Sci U S A. 1974 Aug;71(8):3078–3081. doi: 10.1073/pnas.71.8.3078. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. Gorovsky M. A., Glover C., Johmann C. A., Keevert J. B., Mathis D. J., Samuelson M. Histones and chromatin structure in Tetrahymena macro- and micronuclei. Cold Spring Harb Symp Quant Biol. 1978;42(Pt 1):493–503. doi: 10.1101/sqb.1978.042.01.052. [DOI] [PubMed] [Google Scholar]
  11. Gorovsky M. A., Yao M. C., Keevert J. B., Pleger G. L. Isolation of micro- and macronuclei of Tetrahymena pyriformis. Methods Cell Biol. 1975;9(0):311–327. doi: 10.1016/s0091-679x(08)60080-1. [DOI] [PubMed] [Google Scholar]
  12. Groudine M., Das S., Neiman P., Weintraub H. Regulation of expression and chromosomal subunit conformation of avian retrovirus genomes. Cell. 1978 Aug;14(4):865–878. doi: 10.1016/0092-8674(78)90342-2. [DOI] [PubMed] [Google Scholar]
  13. Jones R. W. Preparation of chromatin containing ribosomal deoxyribonucleic acid from the macronucleus of Tetrahymena pyriformis. Biochem J. 1978 Jul 1;173(1):145–153. doi: 10.1042/bj1730145. [DOI] [PMC free article] [PubMed] [Google Scholar]
  14. Karrer K. M., Gall J. G. The macronuclear ribosomal DNA of Tetrahymena pyriformis is a palindrome. J Mol Biol. 1976 Jun 25;104(2):421–453. doi: 10.1016/0022-2836(76)90280-1. [DOI] [PubMed] [Google Scholar]
  15. Kornberg R. D. Structure of chromatin. Annu Rev Biochem. 1977;46:931–954. doi: 10.1146/annurev.bi.46.070177.004435. [DOI] [PubMed] [Google Scholar]
  16. Laemmli U. K. Cleavage of structural proteins during the assembly of the head of bacteriophage T4. Nature. 1970 Aug 15;227(5259):680–685. doi: 10.1038/227680a0. [DOI] [PubMed] [Google Scholar]
  17. Levinger L. F., Carter C. W., Jr Superstructural differences between chromatin in nuclei and in solution are revealed by kinetics of micrococcal nuclease digestion. J Biol Chem. 1979 Oct 10;254(19):9477–9487. [PubMed] [Google Scholar]
  18. Maniatis T., Jeffrey A., Kleid D. G. Nucleotide sequence of the rightward operator of phage lambda. Proc Natl Acad Sci U S A. 1975 Mar;72(3):1184–1188. doi: 10.1073/pnas.72.3.1184. [DOI] [PMC free article] [PubMed] [Google Scholar]
  19. Mathis D. J., Gorovsky M. A. Subunit structure of rDNA-containing chromatin. Biochemistry. 1976 Feb 24;15(4):750–755. doi: 10.1021/bi00649a005. [DOI] [PubMed] [Google Scholar]
  20. McCarty K. S., Jr, Vollmer R. T., McCarty K. S. Improved computer program data for the resolution and fractionation of macromolecules by isokinetic sucrose density gradient sedimentation. Anal Biochem. 1974 Sep;61(1):165–183. doi: 10.1016/0003-2697(74)90343-1. [DOI] [PubMed] [Google Scholar]
  21. Noll M., Kornberg R. D. Action of micrococcal nuclease on chromatin and the location of histone H1. J Mol Biol. 1977 Jan 25;109(3):393–404. doi: 10.1016/s0022-2836(77)80019-3. [DOI] [PubMed] [Google Scholar]
  22. Noll M., Thomas J. O., Kornberg R. D. Preparation of native chromatin and damage caused by shearing. Science. 1975 Mar 28;187(4182):1203–1206. doi: 10.1126/science.187.4182.1203. [DOI] [PubMed] [Google Scholar]
  23. Olins A. L., Carlson R. D., Wright E. B., Olins D. E. Chromatin nu bodies: isolation, subfractionation and physical characterization. Nucleic Acids Res. 1976 Dec;3(12):3271–3291. doi: 10.1093/nar/3.12.3271. [DOI] [PMC free article] [PubMed] [Google Scholar]
  24. Piper P. W., Celis J., Kaltoft K., Leer J. C., Nielsen O. F., Westergaard O. Tetrahymena ribosomal RNA gene chromatin is digested by micrococcal nuclease at sites which have the same regular spacing on the DNA as corresponding sites in the bulk nuclear chromatin. Nucleic Acids Res. 1976 Feb;3(2):493–505. doi: 10.1093/nar/3.2.493. [DOI] [PMC free article] [PubMed] [Google Scholar]
  25. Sedat J., Manuelidis L. A direct approach to the structure of eukaryotic chromosomes. Cold Spring Harb Symp Quant Biol. 1978;42(Pt 1):331–350. doi: 10.1101/sqb.1978.042.01.035. [DOI] [PubMed] [Google Scholar]
  26. Southern E. M. Detection of specific sequences among DNA fragments separated by gel electrophoresis. J Mol Biol. 1975 Nov 5;98(3):503–517. doi: 10.1016/s0022-2836(75)80083-0. [DOI] [PubMed] [Google Scholar]
  27. Wild M. A., Gall J. G. An intervening sequence in the gene coding for 25S ribosomal RNA of Tetrahymena pigmentosa. Cell. 1979 Mar;16(3):565–573. doi: 10.1016/0092-8674(79)90030-8. [DOI] [PubMed] [Google Scholar]
  28. Yao M. C., Blackburn E., Gall J. G. Amplification of the rRNA genes in Tetrahymena. Cold Spring Harb Symp Quant Biol. 1979;43(Pt 2):1293–1296. doi: 10.1101/sqb.1979.043.01.147. [DOI] [PubMed] [Google Scholar]

Articles from Proceedings of the National Academy of Sciences of the United States of America are provided here courtesy of National Academy of Sciences

RESOURCES