Medicine >> OtherTelomerase and Human Fibroblast Cell Life In Vitroby Michael Field
Submitted : Spring 2012 Telomeres are caps of repeating non-coding DNA that form the end of each human chromosome. At the end of each replication cycle the very end of the telomere is removed to “wrap” the DNA back into its chromosomal shape. The telomere is degraded at the end of every cycle because in DNA replication the lagging strand of replication cannot be completed properly without this process taking place. However it has been found that the ends of a chromosome will stick together, and immediately cause cell death, without a telomere (1). There is only one known way to prevent a telomere from completely degrading. An enzyme active in the nucleus of human cells has been discovered that replenishes the ends of telomeres, and preventing telomere depletion from causing of cell death to occur. It has also been determined that the enzyme, telomerase is not active in human somatic cells, as they appear in the human body. When human cells are modified to produce telomerase, the human somatic cells do not present the typical signs of aging such as reduced replication rate (3). Telomerase prevents a cell from reaching cell death by adding non-coding DNA codes to the end of telomeres. It has also been determined that cell that present positive telomerase activity are not stunted by typical cell aging (4). This discovery has very broad implications on the human population for if a human cell can be made to live indefinitely, then why not an entire human being. Though it is clear that telomerase alone cannot completely defeat aging, it can help hold back the tide. Related Links:
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