Alternative Splicing of a Novel Inducible Exon Diversifies the CASK Guanylate Kinase Domain
Figure 5
Exon skipping is induced by factors with conserved motifs in close proximity to E24a. (a) The CASK_E24a splicing reporter is shown with the motif copy number for each splicing factor tested in the experiment represented by tick marks in the most highly conserved block corresponding to Supplementary Figure S5: upstream intron (up int), exon, and downstream intron (dn int). (b) Gel panels display the products from splicing reporter assays (E24a included and skipped) in N18TG2 and C2C12 cells. Transfections were performed with protein expression plasmids: hnRNP H (lanes 2, 9), CUGBP2 (lanes 3, 10), Nova (lanes 4, 11), PTB (lanes 5, 12), SC35 (lanes 6, 13), and ASF/SF2 (lanes 7, 14). Control samples (ctrl) were transfected with an equivalent amount of empty vector plasmid (lanes 1, 8). Bar graphs illustrate the % exon inclusion values for the gel panels above. (c) The CASK_E24a splicing reporter was cotransfected into C2C12 cells with an empty vector control (Ctrl), hnRNP L, or SRp75 protein expression vectors. Transfections and RT-PCR amplification from the flanking exons were carried out in triplicate. Percent exon inclusion is indicated below the gel panel, ± standard deviation.
