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. 1994 Mar 1;91(5):1955–1958. doi: 10.1073/pnas.91.5.1955

Lack of telomere shortening during senescence in Paramecium.

D Gilley 1, E H Blackburn 1
PMCID: PMC43283  PMID: 8127914

Abstract

Paramecium tetraurelia cells have a limited clonal life span and die after approximately 200 fissions if they do not undergo the process of autogamy or conjugation. To test the possibility that cellular senescence of this species is caused by telomere shortening, we analyzed the genomic DNA of the macronucleus during the clonal life span of P. tetraurelia. We found that telomeric DNA sequences were not shortened during the interval of decreased fission rate and cellular death, defined as senescence in these cells. However, the mean size of the macronuclear DNA was markedly decreased during the clonal life span. We present a model that expands upon previous proposals that accumulated DNA damage causes cellular senescence in P. tetraurelia.

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Selected References

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

  1. Allsopp R. C., Vaziri H., Patterson C., Goldstein S., Younglai E. V., Futcher A. B., Greider C. W., Harley C. B. Telomere length predicts replicative capacity of human fibroblasts. Proc Natl Acad Sci U S A. 1992 Nov 1;89(21):10114–10118. doi: 10.1073/pnas.89.21.10114. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Aufderheide K. J. Clonal aging in Paramecium tetraurelia. II. Evidence of functional changes in the macronucleus with age. Mech Ageing Dev. 1986;37(3):265–279. doi: 10.1016/0047-6374(86)90044-8. [DOI] [PubMed] [Google Scholar]
  3. Blackburn E. H. Telomerases. Annu Rev Biochem. 1992;61:113–129. doi: 10.1146/annurev.bi.61.070192.000553. [DOI] [PubMed] [Google Scholar]
  4. Cooke H. J., Smith B. A. Variability at the telomeres of the human X/Y pseudoautosomal region. Cold Spring Harb Symp Quant Biol. 1986;51(Pt 1):213–219. doi: 10.1101/sqb.1986.051.01.026. [DOI] [PubMed] [Google Scholar]
  5. Epstein L. M., Forney J. D. Mendelian and non-mendelian mutations affecting surface antigen expression in Paramecium tetraurelia. Mol Cell Biol. 1984 Aug;4(8):1583–1590. doi: 10.1128/mcb.4.8.1583. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Forney J. D., Blackburn E. H. Developmentally controlled telomere addition in wild-type and mutant paramecia. Mol Cell Biol. 1988 Jan;8(1):251–258. doi: 10.1128/mcb.8.1.251. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Fraga C. G., Shigenaga M. K., Park J. W., Degan P., Ames B. N. Oxidative damage to DNA during aging: 8-hydroxy-2'-deoxyguanosine in rat organ DNA and urine. Proc Natl Acad Sci U S A. 1990 Jun;87(12):4533–4537. doi: 10.1073/pnas.87.12.4533. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Gilley D., Preer J. R., Jr, Aufderheide K. J., Polisky B. Autonomous replication and addition of telomerelike sequences to DNA microinjected into Paramecium tetraurelia macronuclei. Mol Cell Biol. 1988 Nov;8(11):4765–4772. doi: 10.1128/mcb.8.11.4765. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Harley C. B., Futcher A. B., Greider C. W. Telomeres shorten during ageing of human fibroblasts. Nature. 1990 May 31;345(6274):458–460. doi: 10.1038/345458a0. [DOI] [PubMed] [Google Scholar]
  10. Holmes G. E., Bernstein C., Bernstein H. Oxidative and other DNA damages as the basis of aging: a review. Mutat Res. 1992 Sep;275(3-6):305–315. doi: 10.1016/0921-8734(92)90034-m. [DOI] [PubMed] [Google Scholar]
  11. Holmes G. E., Holmes N. R. Accumulation of DNA damages in aging Paramecium tetraurelia. Mol Gen Genet. 1986 Jul;204(1):108–114. doi: 10.1007/BF00330196. [DOI] [PubMed] [Google Scholar]
  12. Lundblad V., Szostak J. W. A mutant with a defect in telomere elongation leads to senescence in yeast. Cell. 1989 May 19;57(4):633–643. doi: 10.1016/0092-8674(89)90132-3. [DOI] [PubMed] [Google Scholar]
  13. Smith-Sonneborn J. DNA repair and longevity assurance in Paramecium tetraurelia. Science. 1979 Mar 16;203(4385):1115–1117. doi: 10.1126/science.424739. [DOI] [PubMed] [Google Scholar]
  14. Yu G. L., Bradley J. D., Attardi L. D., Blackburn E. H. In vivo alteration of telomere sequences and senescence caused by mutated Tetrahymena telomerase RNAs. Nature. 1990 Mar 8;344(6262):126–132. doi: 10.1038/344126a0. [DOI] [PubMed] [Google Scholar]

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