I did another round of DNA and RNA extractions yesterday. First I did some RNA extractions on some frozen tissues that consisted of only tentacle crowns, the idea being that these tissues will be the most enriched with symbionts. I used the Qiagen RNeasy kit followed by quantification using the Qubit RNA HS assay, with 1 ul of sample. Many of these preps had RNA concentrations over the detection limit so they will need to be diluted.
Note: sample G3 was extracted on 8/28/18 and quantified the same day. Also note these are labeled “RNA-2″.
Sample | Vol ul | RNA ng/ul |
A1 | 40 | 93 |
A3 | 40 | too high |
A4 | 40 | 190 |
G1 | 40 | too high |
G2 | 40 | too high |
G4 | 40 | 172 |
G3 | 40 | 46 |
Next I wanted to examine the effect of tissue concentration on DNA extractions since my previous round of extractions gave very low yields. I wondered if I had used either too much or too little tissue. These samples were ground in liquid nitrogen and I have less experience extracting DNA from such samples. It is very possible that the ground samples extract much more efficiently and that I was using too much sample. Unfortunately the results are not totally clear, as the initial quantity of ground tissue did not seem to have a major effect on DNA yield. My hypothesis is that the low quantities of tissue may have saturated the columns and therefore the higher quantities of tissue gave similar yields due to the combined effects of more DNA and yet more saturation or clogging of the membranes. The DNA was eluted with a single pass of 50 ul AE buffer and quantified using the Qubit DNA HS kit with 3 ul of sample.
Sample | Vol ul | DNA ng/ul |
A4-L | 50 | 29.5 |
A4-M | 50 | 28.6 |
A4-H | 50 | 26.3 |