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Telomeres Clarification

  1. Jun 19, 2012 #1
    I know that telomeres are found on the ends of DNA molecules as stated by my notes. But i was wondering if they are only found on the 3' ends or both 5' and 3' because since DNA is double stranded, if it were to be found on both 5' and 3', one parental strand will be
    5'-TTAGGGTTAGGGTTAGGG█████████TTAGGGTTAGGGTTAGGG-3'. By complementary base pairing, the other parental strand will be
    3'-AATCCCAATCCCAATCCC█████████AATCCCAATCCCAATCCC-5' whereby there is no telomere repeat at the ends.

    Please clarify this doubt thanks! :)
  2. jcsd
  3. Jun 19, 2012 #2


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    Telomeric sequences are found on both the 5' and 3' ends of the DNA. The telomeric sequence on the 3' end is slightly longer than the sequence on the 5' end, so there will be a single-stranded overhang on the 3' end. This single stranded region is used to form a looped structure that protects the end of the DNA from recognition by the DNA repair machinery (http://pmgm2.stanford.edu/biochem118/Papers/DNA%20Papers/Telomerase%20D-Loop-TLoop.pdf [Broken])
    Last edited by a moderator: May 6, 2017
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