Telomerase-mediated telomere addition in vivo requires DNA primase and DNA polymerases alpha and delta

Cell. 1999 Dec 23;99(7):723-33. doi: 10.1016/s0092-8674(00)81670-0.


To better understand the requirements for telomerase-mediated telomere addition in vivo, we developed an assay in S. cerevisiae that creates a chromosome end immediately adjacent to a short telomeric DNA tract. The de novo end acts as a telomere: it is protected from degradation in a CDC13-dependent manner, telomeric sequences are added efficiently, and addition occurs at a faster rate in mutant strains that have long telomeres. Telomere addition was detected in M phase arrested cells, which permitted us to determine that the essential DNA polymerases alpha and delta and DNA primase were required. This indicates that telomeric DNA synthesis by telomerase is tightly coregulated with the production of the opposite strand. Such coordination prevents telomerase from generating excessively long single-stranded tails, which may be deleterious to chromosome stability in S. cerevisiae.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Carrier Proteins / metabolism
  • Cell Cycle / physiology
  • Cyclin B / metabolism
  • DNA Polymerase I / metabolism*
  • DNA Polymerase III / metabolism*
  • DNA Primase / metabolism*
  • Nocodazole / pharmacology
  • Saccharomyces cerevisiae / metabolism*
  • Saccharomyces cerevisiae Proteins*
  • Tandem Repeat Sequences
  • Telomerase / metabolism*
  • Telomere / metabolism
  • Telomere-Binding Proteins


  • Carrier Proteins
  • Cyclin B
  • RIF2 protein, S cerevisiae
  • Saccharomyces cerevisiae Proteins
  • Telomere-Binding Proteins
  • DNA Primase
  • Telomerase
  • DNA Polymerase I
  • DNA Polymerase III
  • Nocodazole