Telomere
DETelomer
Reviewed by Maurice Lichtenberg
Telomeres are repetitive TTAGGG DNA sequences capping the ends of linear chromosomes, protecting them from degradation, fusion, and erroneous repair. Each somatic cell division shortens telomeres because DNA polymerase cannot fully replicate chromosome ends. Critically short telomeres trigger senescence or apoptosis. Telomere attrition is one of the twelve hallmarks of aging and is associated with cardiovascular disease, immune decline, and reduced regenerative capacity.
Sources
- Greider CW, Blackburn EH. (1985). Identification of a specific telomere terminal transferase activity in Tetrahymena extracts. *Cell*doi:10.1016/0092-8674(85)90170-9
- Epel ES, Blackburn EH, Lin J, Dhabhar FS, Adler NE, Morrow JD, Cawthon RM. (2004). Accelerated telomere shortening in response to life stress. *Proceedings of the National Academy of Sciences USA*doi:10.1073/pnas.0407162101
- Moyzis RK, Buckingham JM, Cram LS, Dani M, Deaven LL, Jones MD, Meyne J, Ratliff RL, Wu JR. (1988). A highly conserved repetitive DNA sequence, (TTAGGG)n, present at the telomeres of human chromosomes. *Proceedings of the National Academy of Sciences USA*doi:10.1073/pnas.85.18.6622