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Updated: Jun 24, 2026

Utilizing Murine Inducible Telomerase Alleles in the Studies of Tissue Degeneration/Regeneration and Cancer
08:34

Utilizing Murine Inducible Telomerase Alleles in the Studies of Tissue Degeneration/Regeneration and Cancer

Published on: April 13, 2015

A p53-dependent response limits epidermal stem cell functionality and organismal size in mice with short telomeres

Ignacio Flores1, Maria A Blasco

  • 1Telomeres and Telomerase Group, Molecular Oncology Program, Spanish National Cancer Centre (CNIO), Madrid, Spain.

Plos One
|March 20, 2009
PubMed

Insights

Removing the p53 gene rescues dwarfism and restores tissue regeneration in mice lacking telomerase. This highlights a p53-dependent senescence pathway limiting stem cell function and tissue repair.

Area of Science:

  • Cell Biology
  • Genetics
  • Developmental Biology

Background:

  • Telomere maintenance is crucial for organ size and function, especially in high-turnover tissues.
  • Telomerase deficiency in mice leads to dwarfism and impaired tissue regeneration, including skin defects.
  • Activated p53 in these mice is implicated in cellular senescence and apoptosis, contributing to observed phenotypes.

Purpose of the Study:

  • To investigate the role of p53 in the phenotypes associated with telomere dysfunction.
  • To determine if p53 abrogation can rescue the regenerative capacity of telomerase-deficient mice.
  • To elucidate the mechanisms by which p53 impacts stem/progenitor cell function in aging and regeneration.

Main Methods:

  • Genetic ablation of the p53 gene in telomerase-deficient mice.
  • Assessment of physical characteristics, including body size and skin phenotypes (hair growth, wound healing).
  • Evaluation of epidermal stem cell (ESC) function in vitro (clonogenic assays) and in vivo (mobilization).
  • Analysis of senescence and apoptosis markers in various tissues.

Main Results:

  • p53 abrogation rescued the dwarf phenotype and restored skin regeneration, including hair growth and wound healing.
  • p53-deficient, telomerase-deficient mice exhibited restored ESC mobilization and improved ESC clonogenic activity.
  • The recovery of ESC function was associated with reduced senescence markers and increased proliferation in skin and kidney, without altering apoptosis rates.

Conclusions:

  • A p53-dependent senescence response in stem/progenitor cells with dysfunctional telomeres limits their contribution to tissue regeneration.
  • Targeting the p53 pathway may offer therapeutic strategies to enhance tissue repair and combat age-related decline in regenerative capacity.
  • Dysfunctional telomeres trigger a p53-mediated senescence that impairs tissue fitness and regeneration.

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