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bioRxiv · 10.1101/2023.02.03.527016

Deletion of MEC1 suppresses replicative senescence of the cdc13-2 mutant in Saccharomyces cerevisiae

Yao, Y.·Fekete-Szücs, E.·Rosas Bringas, F. R.·Chang, M.
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Abstract

In Saccharomyces cerevisiae, telomerase recruitment to telomeres depends on a direct interaction between Cdc13, a protein that binds single-stranded telomeric DNA, and the Est1 subunit of telomerase. The cdc13-2 allele disrupts telomerase association with telomeres, resulting in progressive telomere shortening and replicative senescence. The Mec1/ATR kinase is both a positive and negative regulator of telomerase activity, and is required for the cell cycle arrest in telomerase-deficient senescent cells. In this study, we find that deletion of MEC1 suppresses the replicative senescence of cdc13-2. This suppression is dependent on telomerase, indicating that Mec1 antagonizes telomerase-mediated telomere extension in cdc13-2 cells to promote senescence.

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Yao, Y., Fekete-Szücs, E., Rosas Bringas, F. R., Chang, M.. 2023-02-08. Deletion of MEC1 suppresses replicative senescence of the cdc13-2 mutant in Saccharomyces cerevisiae. https://doi.org/10.1101/2023.02.03.527016

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