Telomerase Control by Epigenetic Processes in Cellular Senescence

  • Huaping Chen
  • Trygve O. Tollefsbol


Cellular senescence is a controversial process that can prevent age-related diseases such as cancer while also promoting the aging process. A number of genes, such as those of oncogenes and tumor suppressors, have been shown to be of high importance in this process. Telomerase is a crucial enzyme that plays a pivotal role in cellular senescence by maintaining the stability of the genome. Five components of telomerase have been discovered so far, namely hTERT which is the catalytic subunit of telomerase, hTR which provides the RNA template for hTERT, a protein termed dyskerin which binds to hTR, and two additional proteins termed pontin and reptin which can assist the assembly of telomerase. Genetic control of these genes in cellular senescence has been investigated widely and many advances have been made in understanding the basis of the control of these genes. Epigenetic processes are important mechanisms that regulate the expression of genes and epigenetic control has also been shown to play an important role in cellular senescence. Our current insights on telomerase control by epigenetic processes in cellular senescence are reviewed in this chapter.


Telomerase Epigenetic Cellular senescence 


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© Springer Science+Business Media, LLC 2010

Authors and Affiliations

  1. 1.Department of BiologyUniversity of AlabamaBirminghamUSA
  2. 2.Center for Aging and Department of BiologyUniversity of Alabama at BirminghamBirminghamUSA

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