Related Experiment Video

Updated: Jul 11, 2025

Examination of Mitotic and Meiotic Fission Yeast Nuclear Dynamics by Fluorescence Live-cell Microscopy
12:04

Examination of Mitotic and Meiotic Fission Yeast Nuclear Dynamics by Fluorescence Live-cell Microscopy

Published on: June 24, 2019

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Pot1 promotes telomere DNA replication via the Stn1-Ten1 complex in fission yeast

Pâmela C Carvalho Borges1, Chaïnez Bouabboune2, Jose Miguel Escandell1

  • 1Instituto Gulbenkian de Ciência, Oeiras, 2781-901, Portugal.

Nucleic Acids Research
|November 12, 2023
PubMed

Insights

Fission yeast Pot1 protein is essential for telomere DNA replication. Its inactivation leads to telomere loss, but Stn1 protein overexpression rescues this defect, revealing Pot1

Area of Science:

  • Molecular Biology
  • Genetics
  • Cell Biology

Background:

  • Telomeres protect chromosome ends and ensure DNA replication.
  • Pot1 is a telomere-capping protein that prevents DNA damage responses.

Purpose of the Study:

  • To investigate novel functions of fission yeast Pot1.
  • To understand the role of Pot1 in telomere DNA replication using a temperature-sensitive mutant.

Main Methods:

  • Utilized a pot1-1 temperature-sensitive mutant in fission yeast.
  • Analyzed telomere DNA replication, single-stranded DNA (ssDNA) accumulation, and Stn1 recruitment.
  • Assessed the effect of Stn1 overexpression on telomere maintenance and cell viability.

Main Results:

  • Pot1 inactivation impaired telomere DNA replication, causing ssDNA accumulation and telomere loss.
  • Recruitment of Stn1 to telomeres was reduced in pot1-1 mutants.
  • Overexpression of Stn1 rescued telomere loss and restored cell viability.

Conclusions:

  • Pot1 is crucial for telomere DNA replication, likely by recruiting Stn1-Ten1 and Polα-primase via Tpz1.
  • This recruitment promotes lagging-strand DNA synthesis at stalled replication forks.
  • Pot1's role extends beyond capping to actively facilitating replication fork progression at telomeres.

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