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4 Strand Dna Structure

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Science Article:
4-Strand DNA Structure Found in Cells
Everyone knows that DNA is a double-stranded helix that coils on itself to create a dense chromosome. But scientists have discovered that there is a square-shaped type of DNA structure that can be easily created in the lab by folding synthetic DNA strands that are rich in guanine. A type of hydrogen bonding puts these DNA structures together, and scientists believe that these “G-quadruplex structures” occasionally form in DNA of living cells. Shankar Balasubramanian at the University of Cambridge, UK, provided strong evidence that G-quadruplexes are unusual structures might have important biological functions. These structures have protective tips of chromosomes, also known as telomeres. According to this article, there have been studies in cancer cells that have shown that small molecules that bind and stabilize G-quadruplex structures cause DNA damage at telomeres. Scientists believe that these quadruplex structures can be created in other areas in order to regulate cancer-causing genes. Balasubramanian and his colleagues engineered an antibody that tightly fits to the G-quadruplex structures but does not fit with the double helix. He believes that if they learn to better control the genes or other cellular processes that become diseased such as cancer. I found this article very interesting mainly because I had cancer at a young age and knowing that they are getting closer and closer to finding a cure makes me feel better for those in the future that will not go through what I and millions of other cancer patients had to go through. This article was very organized and very informative although it could have gone a little more in depth, explaining words a little better because as a basic biology student I was very lost with what was going on. This article brought in a few different concepts that I can…...

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