Skip to main content
NCBI home page
The Journal of Cell Biology logoLink to The Journal of Cell Biology
. 1981 Aug 1;90(2):515–520. doi: 10.1083/jcb.90.2.515

Tandemly repeated C-C-C-C-A-A hexanucleotide of Tetrahymena rDNA is present elsewhere in the genome and may be related to the alteration of the somatic genome

PMCID: PMC2111854  PMID: 7287815

Abstract

The ribosomal RNA genes of the Tetrahymena macronucleus exist as extrachromosomal, linear molecules. The termini of these molecules have been shown to contain the tandemly repeated hexanucleotide (C-C-C-C-A- A)n. In this study the same or related sequences were found in other locations of the genome. Using the depurination method, we showed that macronuclear DNA contained this sequence even after rDNA had been removed. The sequence was found mainly in the repetitive fraction of the DNA. The presence of this sequence in both the macronucleus and the micronucleus was also shown by Southern hybridization using C-C-C-C-A-A repeat as a probe. Comparison between the hybridization patterns of macronuclei and micronuclei reveals interesting differences. Whereas the two nuclei share the same genetic origin, the majority of the restriction enzyme digestion sites flanking the C-C-C-C-A-A repeat appear to be different. Such a difference was found to be specific for this sequence, because it was not detected when other sequences were used for hybridization. These results suggest that some kind of alteration has occurred in the genome during the formation of the macronucleus, and that the C-C-C-C-A-A repeat may be related to this process.

Full Text

The Full Text of this article is available as a PDF (639.8 KB).

Selected References

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

  1. 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]
  2. Denhardt D. T. A membrane-filter technique for the detection of complementary DNA. Biochem Biophys Res Commun. 1966 Jun 13;23(5):641–646. doi: 10.1016/0006-291x(66)90447-5. [DOI] [PubMed] [Google Scholar]
  3. 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]
  4. Engberg J., Christiansen G., Leick V. Autonomous rDNA molecules containing single copies of the ribosomal RNA genes in the macronucleus of Tetrahymena pyriformis. Biochem Biophys Res Commun. 1974 Aug 19;59(4):1356–1365. doi: 10.1016/0006-291x(74)90463-x. [DOI] [PubMed] [Google Scholar]
  5. Galibert F., Sedat J., Ziff E. Direct determination of DNA nucleotide sequences: structure of a fragment of bacteriophage phiX172 DNA. J Mol Biol. 1974 Aug 15;87(3):377–407. doi: 10.1016/0022-2836(74)90093-x. [DOI] [PubMed] [Google Scholar]
  6. 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]
  7. Gorovsky M. A., Hattman S., Pleger G. L. ( 6 N)methyl adenine in the nuclear DNA of a eucaryote, Tetrahymena pyriformis. J Cell Biol. 1973 Mar;56(3):697–701. doi: 10.1083/jcb.56.3.697. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. 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]
  9. Grunstein M., Hogness D. S. Colony hybridization: a method for the isolation of cloned DNAs that contain a specific gene. Proc Natl Acad Sci U S A. 1975 Oct;72(10):3961–3965. doi: 10.1073/pnas.72.10.3961. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. Helling R. B., Goodman H. M., Boyer H. W. Analysis of endonuclease R-EcoRI fragments of DNA from lambdoid bacteriophages and other viruses by agarose-gel electrophoresis. J Virol. 1974 Nov;14(5):1235–1244. doi: 10.1128/jvi.14.5.1235-1244.1974. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. 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]
  12. Kimmel A. R., Gorovsky M. A. Organization of the 5S RNA genes in macro- and micronuclei of Tetrahymena pyriformis. Chromosoma. 1978 Jun 23;67(1):1–20. doi: 10.1007/BF00285644. [DOI] [PubMed] [Google Scholar]
  13. Lawn R. M., Heumann J. M., Herrick G., Prescott D. M. The gene-size DNA molecules in Oxytricha. Cold Spring Harb Symp Quant Biol. 1978;42(Pt 1):483–492. doi: 10.1101/sqb.1978.042.01.051. [DOI] [PubMed] [Google Scholar]
  14. Philippsen P., Kramer R. A., Davis R. W. Cloning of the yeast ribosomal DNA repeat unit in SstI and HindIII lambda vectors using genetic and physical size selections. J Mol Biol. 1978 Aug 15;123(3):371–386. doi: 10.1016/0022-2836(78)90085-2. [DOI] [PubMed] [Google Scholar]
  15. Rigby P. W., Dieckmann M., Rhodes C., Berg P. Labeling deoxyribonucleic acid to high specific activity in vitro by nick translation with DNA polymerase I. J Mol Biol. 1977 Jun 15;113(1):237–251. doi: 10.1016/0022-2836(77)90052-3. [DOI] [PubMed] [Google Scholar]
  16. 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]
  17. 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]
  18. Williams J. B., Fleck E. W., Hellier L. E., Uhlenhopp E. Viscoelastic studies on Tetrahymena macronuclear DNA. Proc Natl Acad Sci U S A. 1978 Oct;75(10):5062–5065. doi: 10.1073/pnas.75.10.5062. [DOI] [PMC free article] [PubMed] [Google Scholar]
  19. 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]
  20. Yao M. C., Gall J. G. A single integrated gene for ribosomal RNA in a eucaryote, Tetrahymena pyriformis. Cell. 1977 Sep;12(1):121–132. doi: 10.1016/0092-8674(77)90190-8. [DOI] [PubMed] [Google Scholar]
  21. Yao M. C., Gorovsky M. A. Comparison of the sequences of macro- and micronuclear DNA of Tetrahymena pyriformis. Chromosoma. 1974;48(1):1–18. doi: 10.1007/BF00284863. [DOI] [PubMed] [Google Scholar]
  22. Yao M. C., Kimmel A. R., Gorovsky M. A. A small number of cistrons for ribosomal RNA in the germinal nucleus of a eukaryote, Tetrahymena pyriformis. Proc Natl Acad Sci U S A. 1974 Aug;71(8):3082–3086. doi: 10.1073/pnas.71.8.3082. [DOI] [PMC free article] [PubMed] [Google Scholar]

Articles from The Journal of Cell Biology are provided here courtesy of The Rockefeller University Press

RESOURCES