Genome Analysis Reveals Interplay between 5′UTR Introns and Nuclear mRNA Export for Secretory and Mitochondrial Genes
Figure 3
SSCRs derived from 5UI− genes promote mRNA nuclear export.
Capped and polyadenylated transcripts encoding various versions of ftz (see for all modified ftz sequences) were microinjected along with fluorescent 70 kD dextran into the nuclei of NIH 3T3 fibroblasts. After 1 hour, samples were fixed and mRNA was detected by FISH against ftz. (A) Representative micrographs of the mRNA distribution and fluorescent 70 kD dextran (inserts). Scale Bar = 15 µm. (B) Quantification of the cytoplasmic over the total fluorescence signal. Each bar represents an average of three experiments, each of which consisted of 15–30 cells. Error bars represent the standard deviation between the three experiments.