Telomere Length Regulation

Author: Peter Lansdorp1,2
1 Terry Fox Laboratory, British Columbia (BC) Cancer Agency, Vancouver, BC, Canada.
2 Department of Medical Genetics, University of British Columbia, Vancouver, BC, Canada.
Conference/Journal: Front Oncol
Date published: 2022 Jul 4
Other: Volume ID: 12 , Pages: 943622 , Special Notes: doi: 10.3389/fonc.2022.943622. , Word Count: 192

The number of (TTAGGG)n repeats at the ends of chromosomes is highly variable between individual chromosomes, between different cells and between species. Progressive loss of telomere repeats limits the proliferation of pre-malignant human cells but also contributes to aging by inducing apoptosis and senescence in normal cells. Despite enormous progress in understanding distinct pathways that result in loss and gain of telomeric DNA in different cell types, many questions remain. Further studies are needed to delineate the role of damage to telomeric DNA, replication errors, chromatin structure, liquid-liquid phase transition, telomeric transcripts (TERRA) and secondary DNA structures such as guanine quadruplex structures, R-loops and T-loops in inducing gains and losses of telomere repeats in different cell types. Limitations of current telomere length measurements techniques and differences in telomere biology between species and different cell types complicate generalizations about the role of telomeres in aging and cancer. Here some of the factors regulating the telomere length in embryonic and adult cells in mammals are discussed from a mechanistic and evolutionary perspective.

Keywords: development; lifespan; quadruplex DNA; telomerase; telomere length measurements; telomere length regulation; telomere replication; tumor suppression.

PMID: 35860550 PMCID: PMC9289283 DOI: 10.3389/fonc.2022.943622