Unraveling the stepwise maturation of the yeast telomerase including a Cse1 and Mtr10 mediated quality control checkpoint.

ABSTRACT: Telomerases elongate the ends of chromosomes required for cell immortality through their reverse transcriptase activity. By using the model organism Saccharomyces cerevisiae we defined the order in which the holoenzyme matures. First, a longer precursor of the telomerase RNA, TLC1 is transcribed and exported into the cytoplasm, where it associates with the protecting Sm-ring, the Est and the Pop proteins. This partly matured telomerase is re-imported into the nucleus via Mtr10 and a novel TLC1-import factor, the karyopherin Cse1. Remarkably, while mutations in all known transport factors result in short telomere ends, mutation in CSE1 leads to the amplification of Y' elements in the terminal chromosome regions and thus elongated telomere ends. Cse1 does not only support TLC1 import, but al

SUBMITTER: Hirsch AG 

PROVIDER: S-EPMC8590012 | biostudies-literature | 2021 Nov

REPOSITORIES: biostudies-literature