Fig. 5

A schematic model depicting the mechanism of increased expression of the Ovalbumin gene in different cell types in steroid-dependent and –independent manners. The main induction for the expression of the OVA gene in oviduct cells is estrogen that by binding to the SDRE region overcomes the inhibitory circuits exerted by the tissue-specific silencer-like element (TSSL), and negative regulatory element (NRE). The CRISPR/CAS-mediated deletion of the regulatory sequences of the OVA distal promoter (SDRE, NRE, and the linker in between) leads to the expression of the OVA gene in DF1 cells. The CRISPR-mediated interference of regulatory sequences of the NRE element as well leads to an increased expression of the OVA gene in DF1 cells