Cell
Volume 59, Issue 3, 3 November 1989, Pages 521-529
Journal home page for Cell

Article
The human telomere terminal transferase enzyme is a ribonucleoprotein that synthesizes TTAGGG repeats

https://doi.org/10.1016/0092-8674(89)90035-4Get rights and content

Abstract

I have identified an activity in crude HeLa cell extracts that satisfies the requirements for a human telomere terminal transferase or telomerase. It catalyzes the addition of a 6 nucleotide repeating pattern to oligonucleotide primers containing human or nonhuman telomeric repeat sequences. Direct sequence analyses of reaction products reveal the added sequence to be TTAGGG in all cases. Under optimal conditions 65–70 repeats can be synthesized. The enzyme has the properties of a ribonucleoprotein. Telomerase has previously been observed only in ciliated protozoans, which possess 104–107 macronuclear telomeres. The identification of telomerase in HeLa cells with only ∼100 telomeres indicates that telomerase-mediated telomere maintenance is conserved throughout eukaryotes.

References (44)

  • A.R. Krainer et al.

    Normal and mutant human β-globin pre-mRNAs are faithfully and efficiently spliced in vitro

    Cell

    (1984)
  • G.B. Morin et al.

    Mitochondrial telomeres: surprising diversity of repeated telomeric DNA sequences among six species of Tetrahymena

    Cell

    (1988)
  • E.J. Richards et al.

    Isolation of a higher eukaryotic telormere from Arabidopsis thaliana

    Cell

    (1988)
  • J.W. Szostak et al.

    Cloning yeast telomeres on linear plasmid vectors

    Cell

    (1982)
  • G.W. Zieve et al.

    Newly synthesized small nuclear RNAs appear transiently in tbe cytoplasm

    J. Mol. Biol.

    (1988)
  • R.C. Allshire et al.

    Telomeric repeat from T. thermophila cross hybridizes with human telomeres

    Nature

    (1988)
  • R.C. Allshire et al.

    Human telomeres contain at least three types of G-rich repeat distributed nonrandomly

    Nucl. Acids Res.

    (1989)
  • E.H. Blackburn et al.

    Genomic reorganization in ciliated protozoans

    Annu. Rev. Genet.

    (1986)
  • E.H. Blackburn et al.

    The molecular structure of centromeres and telomeres

    Annu. Rev. Biochem.

    (1984)
  • E.H. Blackburn et al.

    Recognition and elongation of telomeres by telomerase

    Genome

    (1989)
  • W.R.A. Brown

    Molecular cloning of human telomeres in yeast

    Nature

    (1989)
  • J.-F. Cheng et al.

    Isolation and characterization of a human telomere

    Nucl. Acids Res.

    (1989)
  • Cited by (1432)

    • Evolution and Functions of Telomeres

      2024, Function and Evolution of Repeated Dna Sequences
    View all citing articles on Scopus
    View full text