Quiescence
Definition
Quiescence is a reversible resting state in which a cell is alive and metabolically active but not actively dividing. Quiescent cells have exited the active cell cycle, often into a state called G0, and can re-enter proliferation when they receive the right signals. This state is especially important for long-lived cells and tissue stem cells that need to remain preserved until repair or regeneration is needed. [1] [2] [3]
Why It Matters in Ageing Research
Quiescence matters because many adult stem cells rely on controlled inactivity to avoid exhaustion, DNA damage, and loss of regenerative potential. With ageing, the regulation of quiescence can become disrupted: some stem cells may fail to activate when repair is needed, while others may leave quiescence too often and lose long-term function. Understanding quiescence helps researchers study stem cell exhaustion, tissue repair, cancer suppression, cellular senescence, and the balance between regeneration and tumour risk. [2] [4] [5]
Common Confusion
- Quiescence is not the same as cellular senescence; quiescent cells can usually re-enter the cell cycle.
- Quiescent cells are not dead or inactive; they maintain regulated biological activity.
- Keeping stem cells quiescent can preserve them, but excessive or poorly regulated quiescence can impair tissue repair.
Related Reading
References
- Coller, H. A., Sang, L., & Roberts, J. M. (2006). A new description of cellular quiescence. https://pubmed.ncbi.nlm.nih.gov/16554874/
- Cheung, T. H., & Rando, T. A. (2013). Molecular regulation of stem cell quiescence. https://pubmed.ncbi.nlm.nih.gov/23962845/
- Yao, G. (2014). Modelling mammalian cellular quiescence. https://pubmed.ncbi.nlm.nih.gov/24731628/
- Urbán, N., & Cheung, T. H. (2021). Stem cell quiescence: The challenging path to activation. https://pubmed.ncbi.nlm.nih.gov/33513359/
- Li, J., & Clevers, H. (2010). Coexistence of quiescent and active adult stem cells in mammals. https://pubmed.ncbi.nlm.nih.gov/20519528/
This glossary entry is provided for educational purposes only and does not constitute medical advice.