brokenportal Posted January 6, 2005 Posted January 6, 2005 I read that cancer cells have their dna wound back wards. Is that true? I doubt it, but maybe somebody can shed some light on that.
brokenportal Posted January 6, 2005 Author Posted January 6, 2005 I read that dna is wound to a specific degree and then as we get older that it unwinds and that that contributes to aging. Is that true?
5614 Posted January 6, 2005 Posted January 6, 2005 well cells in cancer are mutated in any of various ways... that doesnt make the DNA go backwards.
coquina Posted January 6, 2005 Posted January 6, 2005 Maybe this is what you're talking about - from this site: http://claim.springer.de/EncRef/CancerResearch/samples/0001.htm What are telomeres and what do they do? Telomeres are repeated DNA sequences that protect the ends of chromosomes from being treated like a broken piece of DNA needing repair. Without telomeres, the ends of the chromosomes would be "repaired", leading to chromosome fusion and massive genomic instability. Telomeres are also thought to be the "clock" that regulates how many times an individual cell can divide. Telomeric sequences shorten each time the DNA replicates. When at least some of the telomeres reach a critically short length, the cell stops dividing and ages (senesces) which may cause or contribute to some age-related diseases. In cancer, a special cellular reverse transcriptase, telomerase, is reactivated and maintains the length of telomeres, allowing tumor cells to continue to proliferate. Definition: Telomerase (TE-LÓM-ER-ACE) is a ribonucleoprotein enzyme complex (a cellular reverse transcriptase) that maintains chromosome ends and has been referred to as a cellular immortalizing enzyme. Telomerase is a ribonucleoprotein reverse transcriptase enzyme * (composed of both RNA and proteins) that uses its internal RNA component (complementary to the telomeric single stranded overhang) as a template in order to synthesize telomeric DNA (TTAGGG)n, directly onto the ends of chromosomes. Telomerase is present in most fetal tissues, normal adult male germ cells, inflammatory cells, in proliferative cells of renewal tissues, and in most tumor cells. After adding six bases, the enzyme is thought to pause while it repositions (translocates) the template RNA for the synthesis of the next six base pair repeat. This extension of the 3' DNA template end in turn permits additional replication of the 5' end of the lagging strand, thus compensating for the end-replication problem. *reverse transcriptase Definition: enzyme generating a DNA strand from an RNA template in the cytoplasm of a cell infected by a retrovirus; is carried with a retroviral particle.
ecoli Posted January 6, 2005 Posted January 6, 2005 I read that cancer cells have their dna wound back wards. Is that true? I doubt it, but maybe somebody can shed some light on that. Do you mean coded backwards or literally wound backwards?
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