I am about 4 weeks into research (half way done with my research here on campus for the summer) and so close to having mononucleosomes. Since the last time I posted, we have made progress on preparing nucleosomes. The past couple of weeks have consisted of digestion processes with the DNA and running gels to try to figure out if we had nucleosomes in our samples.
Figure 1: Column Trace of NCP (nucleosome core particle) prep samples
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Figure 2: NCP prep gel run with DNA ladder |
Earlier this week I prepared samples to run through 1.2% Agarose gel. As shown in figure 2, we ran 18 samples (4-21) with two DNA ladders on each end. We ran the DNA ladders with the samples because the DNA ladders indicate the length of the nucleosomes. As you can see in figure 2, the red lines indicate how many base pairs there are in the samples, thus distinguishing whether there are mono/di or tri nucleosomes in the samples. As we had assumed, samples 10-14 most likely have mononucleosomes. We were able to conclude this because one nucleosome has ~147 base pairs and the gel we ran shows us that those samples are closest to having the length of a mononucleosome. Even so, Dr. Andresen is going to discuss our results with Dr. Beuttner, in the chemistry department, in order to confirm what samples we should use to proceed. Even so, I believe that we will continue to purify the samples to try to get as many mononucleosomes as we can.