Multiple mechanisms for elongation processivity within the reconstituted tetrahymena telomerase holoenzyme.

ABSTRACT: To maintain telomeres, telomerase evolved a unique biochemical activity: the use of a single-stranded RNA template for the synthesis of single-stranded DNA repeats. High repeat addition processivity (RAP) of the Tetrahymena telomerase holoenzyme requires association of the catalytic core with the telomere adaptor subcomplex (TASC) and an RPA1-related subunit (p82 or Teb1). Here, we used DNA binding and holoenzyme reconstitution assays to investigate the mechanism by which Teb1 and TASC confer high RAP. We show that TASC association with the recombinant telomerase catalytic core increases enzyme activity. Subsequent association of the Teb1 C-terminal domain with TASC confers the capacity for high RAP even though the Teb1 C-terminal domain does not provide a high-affinity DNA interaction sit

SUBMITTER: Min B 

PROVIDER: S-EPMC2878078 | biostudies-literature | 2010 May

REPOSITORIES: biostudies-literature