at the protein and mRNA levels (Fig. 7B, 7C, S7I, S7J). L1-CAM, Hsc70, and GDI as control proteins were not changed. Both manipulations only partially decreased APP levels, as would be expected for an impairment of only one element in the App promoter, and thus provided a specificity control. To the best of our knowledge, CRISPRi has not previously been attempted in vivo, and its applicability for promoter mapping in living mice enables attractive future studies that obviate the need for expensive transgenic experiments. Thus, the AP-1-dependent regulation of APP expression operates physiologically in vivo.
