(A) Schematic diagram of the doxycycline-controllable promoters and the reporter genes that they control. Doxycycline binds to the tTA protein, thereby preventing it from binding to the tet operator.
(B, C) Representative fields of cells from cell lines E-YFP-M1-1x and E-YFP-M1-7x, containing the 1x-tetO and 7x-tetO promoters, respectively, where each mRNA is hybridized to FISH probe P1-TMR and the image was obtained by merging a three-dimensional stack of images.
(D) Two sister cells from cell line E-YFP-M1-7x displaying mRNA hybridized to FISH probe P1-TMR (red) and costained with DAPI (blue). The image represents one focal plane. The scale bars are 5 μm long.