Delivery of yeast telomerase to a DNA break depends on the recruitment functions of Cdc13 and Est1

Mol Cell. 2004 Oct 8;16(1):139-46. doi: 10.1016/j.molcel.2004.09.009.


The yeast single-strand TG-repeat telomere binding protein Cdc13 and the telomerase accessory protein Est1 play essential roles in chromosome end replication. To determine whether a proposed Cdc13-Est1 interaction recruits telomerase (Est2), we used a simplified system in which telomere formation was monitored at an HO-induced DNA double-strand break (DSB). Tethering of either Cdc13 or Est1 adjacent to a DSB promoted telomere formation, and tethering of Est1, even in the absence of a DSB, resulted in the recruitment of Est2. Est1 association with a DSB containing an adjacent short TG-repeat sequence depended on the Cdc13-Est1 interaction affected by cdc13-2 and est1-60 mutations, whereas Cdc13 association did not. Similarly, Est2 binding to the DSB also required the Cdc13-Est1 interaction, but not synthesis of new TG repeats at the break site. These data demonstrate a critical role for Est1 in recruiting telomerase to its site of action, in cooperation with the telomere binding protein Cdc13.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • DNA / metabolism*
  • DNA-Binding Proteins / metabolism
  • Mutation
  • Saccharomyces cerevisiae Proteins / genetics
  • Saccharomyces cerevisiae Proteins / metabolism*
  • Telomerase / metabolism*
  • Telomere-Binding Proteins / genetics
  • Telomere-Binding Proteins / metabolism*
  • Yeasts / genetics
  • Yeasts / metabolism


  • Cdc13 protein, S cerevisiae
  • DNA-Binding Proteins
  • Saccharomyces cerevisiae Proteins
  • Telomere-Binding Proteins
  • high affinity DNA-binding factor, S cerevisiae
  • DNA
  • EST1 protein, S cerevisiae
  • EST2 protein, S cerevisiae
  • Telomerase