Figure 7

QKI-5 regulates self-splicing in vitro in human cells. (a) A schematic of the 3′-UTR of human Hqk gene. Arrows indicate location of primers used for RT-PCR/splicing analysis. (b) (Left) HEK293T cells were transfected with expression vectors encoding green fluorescent protein (GFP) alone or expression vectors for GFP-QKI-5, -QKI-6, -QKI-7, -QKI-5:V157E or -QKI-5:E148G. Total RNA was isolated 72 h later and analyzed by RT-PCR (n = 3). The pixel densities of PCR bands from 3 independent transfections were quantified using ImageJ software, normalized over Hqk constitutive exon 1 and represented as mean ± SEM (One-way ANOVA, **p < 0.01, ***p < 0.001). (c) Protein expression of transfected plasmids in HEK293T cells is determined by immunoblotting using the indicated QKI antibodies or β-actin antibody for equivalent loading. The molecular mass markers are shown on the left in kDa and the migration of the GFP-QKI isoforms indicated on the right.