Regulation of telomere length and function by a Myb-domain protein in fission yeast

Nature. 1997 Feb 20;385(6618):744-7. doi: 10.1038/385744a0.


Telomeres, the specialized nucleoprotein structures that comprise the ends of eukaryotic chromosomes, are essential for complete replication, and regulation of their length has been a focus of research on tumorigenesis. In the budding yeast Saccharomyces cerevisiae, the protein Rap1p binds to telomeric DNA and functions in the regulation of telomere length. A human telomere protein, hTRF (human TTAGGG repeat factor) binds the telomere sequence in vitro and localizes to telomeres cytologically, but its functions are not yet known. Here we use a genetic screen to identify a telomere protein in fission yeast, Taz1p (telomere-associated in Schizosaccharomyces pombe), that shares homology to the Myb proto-oncogene DNA-binding domain with hTRF. Disruption or deletion of the taz1+ gene causes a massive increase in telomere length. Taz1p is required for the repression of telomere-adjacent gene expression and for normal meiosis or sporulation. It may be a negative regulator of the telomere-replicating enzyme, telomerase, or may protect against activation of telomerase-independent pathways of telomere elongation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Chromosomes, Fungal / metabolism
  • Cloning, Molecular
  • DNA-Binding Proteins / chemistry
  • DNA-Binding Proteins / genetics
  • DNA-Binding Proteins / metabolism*
  • Fungal Proteins / chemistry
  • Fungal Proteins / genetics
  • Fungal Proteins / metabolism*
  • Humans
  • Molecular Sequence Data
  • Proto-Oncogene Mas
  • Proto-Oncogene Proteins / chemistry*
  • Proto-Oncogene Proteins c-myb
  • Recombinant Fusion Proteins / genetics
  • Recombinant Fusion Proteins / metabolism
  • Schizosaccharomyces / metabolism*
  • Schizosaccharomyces pombe Proteins*
  • Sequence Homology, Amino Acid
  • Spores, Fungal
  • Telomere / metabolism*
  • Telomere-Binding Proteins*
  • Trans-Activators / chemistry*


  • DNA-Binding Proteins
  • Fungal Proteins
  • MAS1 protein, human
  • Proto-Oncogene Mas
  • Proto-Oncogene Proteins
  • Proto-Oncogene Proteins c-myb
  • Recombinant Fusion Proteins
  • Schizosaccharomyces pombe Proteins
  • Telomere-Binding Proteins
  • Trans-Activators
  • taz1 protein, S pombe

Associated data

  • GENBANK/Y09406