Figure 1.
(A,B) Whole-cell ensemble measurements demonstrate bimodal decay of PTC-containing Gl mRNA. Human U2OS cells were transiently transfected with a plasmid that produced either PTC-containing (TER) or PTC-free (NORM) Gl mRNA from the serum-inducible c-FOS promoter. Thirty-six hours after serum deprivation, GI TER or GI NORM transcription was induced with the addition of serum to 15%. After 30 min, ActD was added, and RNA was purified from cells as a function of time. Using RT-qPCR, the levels of GI TER and GI NORM mRNAs were normalized to the level of GAPDH mRNA. To determine the half-life (t1/2) of TER and NORM mRNAs, the normalized levels of each mRNA (A,B, red and black circles, respectively) were modeled by a weighted fit by the errors to a decay model having either a single component (A, red and black dashed lines) or two components (B, red and black dashed lines) Results from three independently performed experiments ±SEM are shown.