Stochastic Expression of the Interferon-β Gene (original) (raw)
Figure 6
Poly I∶C–induced stochastic IFNβ expression depends on the amounts of poly I∶C and MDA5.
(A) IFNβ/YFP homozygous MEF cells were electroporated with Cy5-labeled poly I∶C, and FACS analysis was carried out 8 h after the electroporation to assay the strength of Cy5 and YFP. The top left panel shows untransfected MEF cells, and the bottom left panel shows the electroporated MEF cells. As indicated by arrows, the two panels to the right represent the “poly I∶C high” and “poly I∶C low” populations, respectively. Data shown are representative of at least three independent experiments. Numbers represent relative percentages. (B) L929-MDA5 or L929-RIG-I stable transfectants were stimulated with tetracycline (Tet) for 24 h followed by transient transfection with poly I∶C. 6 h after transfection, cells were fixed, followed by RNA ISH to detect IFNβ mRNA. (C) Bar plots representing the percentage (mean ± standard deviation) of cells expressing IFNβ from three independent ISH experiments performed as in (B). At least 400 cells were blindly counted and scored for each category. (D) IFNβ/YFP primary MEFs were fixed 8 h after poly I∶C stimulation. Intracellular staining using MDA5 antibody and FACS analysis were carried out to assay the correlation between the expression levels of IFNβ and MDA5. Data shown are representative of at least three independent experiments. Numbers represent relative percentages. Iso-Ctrl, isotype control.