Comparisons To Southern (1975)

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Article Comparisons to Southern (1975)
Article One
The article “Detection of specific sequences among DNA fragments separated by gel electrophoresis” (1975) by E.M. Southern focuses on the way that the fragments of DNA can be transferred from agarose based gels to cellulose nitrate filters. Then fragments themselves are hybridized to active RNA. E.M. Southern’s main influences for the investigation were the studies of Smith and Wilcox (1970), and Kelly and Smith (1970), which showed that the restrictive enzyme Haemophilus influenza was able to make breaks in DNA sequences that were double stranded. The fragments that were made by the enzymes could be separated by electrophoresis in agarose gels, which would elucidate a picture of the fragments
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The scientists were introducing a specified gene sequence into a mammalian embryo to study developmental problems. The insertion of the foreign DNA had to be done when the embryo was still developing so that the DNA could integrate completely into the animal. The objectives of the experiment were to study the processes of gene regulation, and the physiologic role of products of genes more precisely. The methods used in the experiment were to first obtain mice, and have the mice follow a 14:10 hour, light-dark cycle. The female mice were induced to ovulate, and mated with males. After six weeks, the female mice were killed, and had their oviducts opened so that the fertilized eggs could be removed and placed into a dish. The eggs were then stored until they were microinjected. The eggs that survived the injection were stored in another culture dish, and later, implanted. DNA was isolated from the mice after they were born. The DNA from the newborn mice was re-dissolved and digested using restriction enzymes, and electrophoresed. The result of the experiment was that 78 out of the 700 embryos developed into live young. However, only DNA from 2 out of the 78 newborn mice had sequences that strongly hybridized with the probe, …show more content…
There was another discovery where the DNA sequences of HPV 18 were detected in cell lines derived from cervical cancer. The objectives of the investigation that took place in the article “Structure and transcription of human papillomavirus sequences in cervical carcinoma cells” was to analyze the cell lines HeLa, C4-1, and 756, for the structural organization and transcription of the HPV 18 genome. The methods that were used in this investigation was to first isolate RNA and subject it to Northern blot hybridization, with HPV 18 DNA as the probe. The result of the experiment was that the HPV 18 genome was present in a majority, 756, of the cells. In the researchers’ HeLa and C4-1 cells, a 2-3 kilobase segment of HPV 18 specific sequences were mostly in the same regions. Also, poly(A)+ RNA hybridized with the DNA of the HPV 16. The RNA hybridization was found in 2/3 of the cervical carcinoma biopsies that were performed. The article cited the Southern (1975) paper because the researchers utilized the exact process of electrophoresis that was detailed in the Southern (1975) paper. The researchers of this article did a two-dimensional agarose gel electrophoresis to observe the presence of HPV 18

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