4.2. dCas9-TA Activity Calculation

The fold activation of the UbiC promoter by dCas9-TA is calculated as the ratio between the GFP/RFP intensity of CaT-A (RFP+ subset) and the GFP/RFP intensity of CaT-B (RFP+ subset).

Below is an example calculation based on positive control MDA-MB-231-dCas9-VPH cells (see Additional Required Materials to obtain this cell line):

dCas9-TA induced fold induction = 1.282 / 0.084 = 15.3 fold

The activation of the UbiC promoter by dCas9-TA can also be visualized by plotting and superimposing the GFP and RFP intensity of Cat-B (RFP+ subset) and Cat-A (RFP+ subset) samples, as shown below:

As an additional negative control (optional), the parental cell line of the dCas9-TA cells can be transduced with CaT-A and CaT-B viruses. For cells without dCas9-TA, the fold activation should be close to 1.