Abstract
The ends of linear chromosomes are capped by specialized nucleoprotein structures termed telomeres. Telomeres comprise tracts of noncoding hexanucleotide repeat sequences that, in combination with specific proteins, protect against degradation, rearrangement, and chromosomal fusion events. Due to the polarity of conventional DNA synthesis, a net loss of telomeric sequences occurs at each cell division. It has been proposed that this cumulative telomeric erosion is a limiting factor in replicative capacity and elicits a signal for the onset of cellular senescence. To proliferate beyond the senescent checkpoint, cells must restore telomere length. This can be achieved by telomerase, an enzyme with reverse-transcriptase activity. This enzyme is absent in differentiated somatic tissues, but telomerase reactivation has been detected in most tumors. Much investigative effort is focusing on telomere dynamics with a view to possible manipulation of cellular proliferative potential. In this article, we review the role of telomeres and telomerase in senescence and tumor progression, and we discuss the potential use of telomerase in diagnosis and treatment.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
