Recombinant DNA vs. RNA interference

Chapter 2 in Genentech talked heavily on the applications of Recombinant DNA. The main application discussed was an easier way to produce the hormone insulin for people suffering from diabetes. In molecular genetics, the course offered here at loyola, one of the experiments done within the semester is making our own recombinant DNA. We actually did Boyer’s experiment and tested whether or not it was successful by running the samples on a gel and on petri dishes. When we used the petri dishes we streaked the plates with our recombinant DNA and did a blue/white screening to test the colonies that contained our plasmid. The colonies that remained white were and indication of our recombinant DNA due to the inactivation of a-galactosidase. While reading Genentech reminded me of this experiment and also another involving RNA interference.

As rRNA is used to produce a certain protein as RNA interference is used to stop the production of a certain protein. The two types that we studied were microRNA (miRNA) and small interfering RNA (siRNA). They both have different properties as to what type of sequences they bind to. Basically, they are small sequences that are able to bind to other sequences to prevent the translation of their amino acids, aka protein. This is super cool! It makes me wonder if this technology could possibly be used in the future to fight disease. For example, cancer therapy. Hypothetically, if scientist were able to program a specific miRNA to target the protein production of a cancer cell, it may be able to stop the proliferation of the cell. Without vital protein production then the cell will die, possibly killing off the cancer. It seems like something that should be researched.

Recombinant DNA vs. RNA interference

Fingerprinting

After reading Chapter 4 of Pointing from the Grave, it really shed light on the complexity and developments in the field of forensic science. Of course, I was familiar with the use of lifting finger prints and matching them from shows like CSI. However, realistically, I never knew how complex the process of collecting and matching fingerprints was. Attached I have posted a link that goes into detail about the of how fingerprints are lifted and examined. While there are many ways to do so, I thought it was very interested how they used immunofluorescent dye stain with orange alternate light source in order to make out a clear picture of the fingerprint. I also found this very related to my independent breast cancer research. In order to test the effects of hypoxia on the aggression of breast cancer cells I carried out an experiment in which I treated the cancer cells with different doses of Cobalt Chloride (which mimics hypoxic conditions) and then died the cells and viewed them under a confocal lens with Texas Red light. This is similar to the way in which the finger prints were stained and viewed under orange light. Overall, I thought it was interesting to see one of the ways in which fingerprints are made out and how it also overlapped with types of experiments I am running as a part of my research.

http://www.forensicsciencesimplified.org/prints/how.html

Fingerprinting

Discovering DNA Sequence

After reading Chapter 3 of Pointing From The Grave, I thought it was very interested that Weinberg devoted this chapter to focusing on the development of DNA, its base pairing, and eventual uses. One part that really stuck out to me was the discussion of running DNA on an agarose gel. Specifically, Weinberg stated that,

“Using a restriction enzyme – a protein that cleaves the DNA strands at designated positions. These lengths would be immobilized by dropping them on one end of the dish of agarose gel to which an electric current would be applied” (p 41).

This discussion of using DNA on a gel in order to discover the sequence stood out to me because it related back to my time in Synthetic Biology. Today, we use gel electrophoresis, similar to the one described in the novel as a southern blot, to detect the sequences of DNA in our whole fragment. In Synthetic biology specifically we used restriction enzymes to cut as specific points in order to understand banding pattern and sequences present in yeast. In addition, this correlates to what I learned in Cancer Biology and what I am doing in my independent research of breast cancer cells. Essentially, we used Western blot to understand protein expression to characterize cancer cells and their aggression. Overall, it is very interesting to see the development of DNA and the technologies associated with it in different types of labs, whether it was synthetic or cancer related.

Discovering DNA Sequence