This summer, I’ve been learning how to use Prism to produce graphs. Our lab usually uses Excel for basic data analysis, but we needed to present data in ways that Excel couldn’t handle, so I decided to learn to use Prism, which can do a lot more than Excel.
At this point, I have a pretty good idea of how to use Prism. This week, we had to analyze data from an experiment that uses F9 cells (mouse testicular carcinoma cells) expressing RARE-LacZ to quantify the amount of retinoic acid present in embryos of different genotypes. Retinoic acid responsive element (RARE) is bound by an RAR/RXR heterodimer and, in the presence of retinoic acid, the heterodimer stimulates transcription of downstream targets – in this case, LacZ. This allows us to perform X-gal staining on our cells. More staining means more retinoic acid.
In order to quantify the amount of retinoic acid in each of the embryos we tested, we also used nine different standards. I used Prism to fit these standard points to a line and interpolated the concentrations of retinoic acid for each unknown point (Prism can do this automatically!).
I’ve attached an image of one of the standard wells. The blue staining indicates that LacZ is being transcribed, suggesting that retinoic acid is present.