Fig 2: Nonsense-mediated degradation of a β-GLOBIN luciferase reporter is inhibited by ASOs targeting NMD factors. Mouse MHT cells stably expressing a PTC-containing β-GLOBIN Renilla luciferase reporter were treated with ASOs targeting mouse NMD factors Upf1, Upf2, Smg1, Smg6, Upf3b, Smg5, Smg7, Smg8, Smg9, or Upf3a, by free uptake at the indicated concentrations for 72 h. Results are presented as means ± standard errors (n = 3). a qPCR analysis of the mRNA levels of each NMD factor after ASO treatment. Mouse Gapdh mRNA was used as endogenous control. The mRNA level of each NMD factor in untreated (NT) MHT cells was set as 1. b Relative luciferase activity after ASO treatment. The luciferase activity from the PTC-containing β-GLOBIN Renilla construct was normalized to the Firefly luciferase signal, which was also stably expressed in the MHT cells. Luciferase activity in untreated MHT cells was set as 1. Results were grouped in three categories: Robust, Modest or Passive regulators. Statistical significance was determined using a two-way ANOVA and Dunnett’s multiple comparison test in Prism. All groups were compared to NT group within each measurement. * p < 0.05; ** p < 0.01; *** p < 0.001; **** p < 0.0001