FIG. 7.
A 24-nt intronic sequence is sufficient for regulation of alternative splicing by Nova-1 in a heterologous context. (A) DNA sequences derived from GABAARγ2 intron 9 contained within the chimeric minigenes used in panels B and C. Numbers specify the lengths (in base pairs) of the GABAARγ2 intronic regions cloned into the β-globin minigene. The star denotes the presence of four C-to-A mutations within the 24-nt GABAARγ2 sequence. (B and C) The chimeric minigenes depicted in panel A were cotransfected into 293T (B) or N2A (C) cells with increasing amounts (0, 0.5, or 2.0 μg) of pNova-1, and spliced products were measured by RT-PCR and phosphorimage analysis as described for Fig. 2. The titration of transfected pNova-1 expression was monitored by Western blotting (data not shown). Representative autoradiographs are shown at the left side of each panel; graphs summarize data from three independent transfections. The bars represent the ratios of L/S spliced products ± standard deviations.