FIGURE 7.

Identification of a differential nuclear polyadenylation of C/EBPβ mRNA from βwt and βd/s cell lines. Poly(A) tail lengths on βwt and βd/s were determined by reverse transcription-PCR poly(A) analysis of a preparation of total nuclear RNA from βwt and βd/s cell lines. Reverse transcription was primed with an oligo(dT) primer/adapter as described, and poly(A) tail lengths on the βwt and βd/s mRNAs were determined by PCR using a 5′-³²P-labeled primer/adapter for the reverse primer and a gene-specific primer for the forward primer. The products of the PCRs were visualized by autoradiography after electrophoresis on 6% polyacrylamide/urea gels. Size markers are in nucleotides. The regions corresponding to polyadenylation of the C/EBPβ mRNA are boxed for comparison. Lanes 2, 4, and 6 contain the full PCRs, whereas lanes 1, 3, and 5 contain 20% of the reactions. The autoradiogram presented is representative of an experiment performed 3 times with similar results.