FIG. 6.

The DICE-2R motif stabilizes a human α-globin mRNA lacking its cognate PR determinant. The C-rich PR stabilization determinant in the α^WT 3′-UTR was replaced with the DICE-2R determinant (α^2R) or mutant DICE-2Rm determinant (α^2Rm) (Fig. 1A). The two corresponding genes were placed under transcriptional control of a Tet-controlled promoter. Each construct was transfected into MEL/tTA cells followed by a 4-h transcriptional pulse and subsequent chase. RPA detected the remaining mRNA at each time point. The α^2R or α^2Rm signals were normalized to the internal mGAPDH control and to cell number (see Materials and Methods). The computed half-life is shown in the box, and a representative gel is shown under the decay curve. The data points for the α^2R and α^2Rm mRNAs represent the results from nine and seven independent studies, respectively.