Figure 6. Compensatory mutations within sections 3 and 4 together restore minus beta splicing of the mutant block 6 repeats.

The splicing of minigenes containing wild-type or mutant repeats, with or without replacement of sections containing compensatory mutations, are shown together with the quantification of the full-length and minus beta isoforms. Alternative splicing is abolished using a block 6 repeat sequence containing a single-nucleotide mutation, which is restored by introducing compensatory mutations when sections 3 and 4 are combined. Data are from Hela FRT clone 8 cells stably transfected with the minigenes (n=3). Error bars represent mean±standard deviation. The results are replicated in three separate transfections in two Hela FRT clones. Minus alpha is a minor alternative splice form that skips the first 36 nt of exon 6. Images of the full-length gels are provided in Supplementary Figs 1 and 2.