Share some knowledge on telomeres? Relationships with age & cancer?

Question

I'm more specifically look for someone to "break down" the text on Wikipedia's article on telomeres... I know that they shorten a bit with ech time a cell is replicated, but other than that I'm kind of lost...

I honestly have read a bit, but I'm still confused..

Help?

^_^

Answer 1

Hi Sasuke. I have never read a simple and clear-cut description of telomeres, so I can understand your confusion and frustration.

Telomeres are 'tails' of DNA on the end of the chain of DNA that makes up each chromosome. As you are aware, the telomeres shorten with each replication of the chromosome. When the telomeres get 'short enough' they trigger the cell to commit apoptosis (organized cell death).

Cancer cells produce telomerase, an enzyme that 'regrows' telomeres. Because telomerase prevents the shortening of telomeres in cancer cells, the cells become "immortal" and can survive for much longer periods of time than normal cells. So, the production of telomerase is vital for the development and survival of a cancerous tumor.

Hope this helps you. Best wishes and good luck.

P.S. All human cells contain the gene for telomerase. This enzyme appears to be vital in early development, but becomes dormant (repressed) after its initial function. Cancer cells "de-repress" the gene and, thus, are able to make the enzyme.

Answer 2

THE DIFFERENCE BETWEEN TELOMERES AND TELOMERASE AND THE ROLE THEY PLAY IN AGING.

In 1971 Dr. Alexey M. Olovnikov published a theory in which he first formulated the DNA end (telomeres) replication problem and explained how it could be solved. The solution to this problem also provided an explanation for the Hayflick Limit (the 125 year ceiling on the human lifespan), which underpins the discovery of in vitro and in vivo cell senescence (deterioration). Telomeres are a repeating DNA sequence of 6 RNA/DNA pairings, (A-T,A-T,T-A, C-G,C-G,C-G). When a cell divides, the new DNA cannot complete it's final pairing thus telomeres get shorter with each cell division. We are conceived with 15,000 pairs of telomeres, are born with 10,000 pairs and generaly die when we hit 5000 pairs. Telomerase is an enzyme which when activated in the cell provides a sort of "platform" as it where, so that the new DNA strand is able to complete. The telomerase enzyme attaches to the end of the chromosome; complementary bases to the RNA template are added on the 3' end of the DNA strand. Once the lagging strand is elongated by telomerase, DNA polymerase can add the complementary nucleotides to the ends of the chromosomes and the telomeres can finally be replicated.
. It used to be thought that telomerase production promoted cancer since cancer cells themselves have the telomerase enzyme turned on, however the latest research by Dr. William Andrews, the discoverer of the telomerase enzyme, has shown the opposite to be true. Ctiating telomerase in healthy cells around a tumer will cause a cancerous tumor to reduce. This is due mainly to boost in the bodies natural immune functions. For a free 30 day seminar on telomeres try https://christopher-george.leadpages.net/telomere-report/

Answer 3

Doctor J's got it bang on. Think of your chromosomes as strands of hair. When the replication process happens in the cell, they are physically moving around, and sometimes the ends, or telomeres, get tangled up and sheer off like strands of hair.