When performing CRISPRa, what level of overexpression should I expect?
The level of gene activation depends very much on the basal expression of the gene, and is therefore cell-line specific. For genes that are either not expressed or expressed at a low level, we generally see high fold activation (100 to 10,000 fold over NTC treated cells). But for genes that are expressed at a high level, CRISPRa causes lower-fold activation (2 -100 fold). Therefore, knowing the level of expression of the gene of interest in your cells can help you gauge the expectation for the fold activation.