Phenol-Chloroform Extraction

     This specific experiment is used to extract mixtures based on their solubilities. In this experiment we used it to extract RNA from DNA and protein. Protein is a non-polar molecule, it will be separated from the DNA which is a polar molecure. The RNA and DNA will end up in the chloroform, which is also polar. And the protein will end up the less polar solution, QIazol. The DNA will separate from RNA as it also moves into QIazol because the negative charge of DNA's backbone will be attracted to the H+ in QIazol. RNA is a single strand, so the exposed nitrogen bases will form hydrogen bonds with chloroform.

      After both solutions were transfered into the test tubes we added them to a centrifuge mixer for 15 min to create the separated layers. Because QIazol has a greater density than chloroform, the QIazol will reside at the bottom of the tube, and will give us easier access to the RNA at the top. Then we can take a pipette and carefully extract the RNA from the test tube.

     We also talked about the role of transcription factors. Transcription factors bind to DNA to make mRNA. DNA is wrapped around a protein histone, and some of it can be unwinded, and on the unwinded DNA there is a start and stop point. There are different stopping places for every different mRNA. And different mRNA's code for different functions and different proteins. There is also something known as "splicing", which means the DNA is cut from the middle, and this creates many message from the same gene.
     The transcription factors can turn on a gene by binding to the DNA, but can also turn off a gene when the gene is not unraveled from the histone leaving there no place for the transcription factor to bind to. Specifically in cancer cells, the transcription factors are always binded to the gene, which is also the reason for the cell's rapid growth. So if the transcription factors can be controled, then the cells would be able to maintain a more stable growth rate.