Fig. 5.

Recruitment of both MS2cp-HuR and MS2cp-p40AUF1 imparts a pH-responsive stabilization of βG-PCK2-MS2 mRNA. Half-life analysis of the βG-PCK2-MS2 reporter RNA in LLC-PK₁-F⁺-9C cells that transiently express MS2cp-HuR and MS2cp-p40AUF1. Cells were maintained in minimal Dox (100 ng/ml) until 70% confluent. Following transient transfection with 2 μg of both expression plasmids, the cells were maintained in normal (pH 7.4) medium minus Dox for 48 h. The cells were then treated with normal (red) or acidic (green) medium for 24 h. RNA was isolated at various times after addition of 1 μg/ml Dox to arrest transcription. The relative levels of β-globin and GAPDH mRNAs were quantified by RT-qPCR. The log of normalized data was then plotted against the time after Dox addition. The reported data are means ± SE of triplicate samples.