FIGURE 2.

Pseudocantharidins promote inclusion of SMN2 exon 7. A, schematic overview of the reporter gene construct. B–G, HEK293 cells were transfected with an SMN2 splicing reporter, consisting of exons 6–8, as well as the included introns that is schematically shown in A. After 4 h, the cells were treated with the compounds at the concentrations indicated. All of the compounds were dissolved in Me₂SO, 0 refers to pure Me₂SO. RNA was isolated after 16 h, and the SMN2 mRNA was amplified using the primers shown in A. The graphs on the right show the percentage of exon 7 inclusion, determined by RT-PCR. B, cantharidin; C, isocantharidin; D, pseudocantharidin A; E, pseudocantharidin B; F, pseudocantharidin C; G, pseudocantharidin D.