Figure 4

Regulation of polyadenylation is independent of splicing. (A) Luciferase assay of BHK-21 cells transfected with pGL3 derivatives. The cleavage and polyadenylation are suppressed by the splicing-incompetent SDm5 mutant. The significances of the reductions by the MSD mutations were calculated by paired two-sample t-test. p-value is indicated. (B) Northern blotting of RNA from BHK-21 cells transfected with pCMVTas and the pGL3 derivatives detected with a probe encompassing nucleotides +1 to +250. Ratios of transcripts uncleaved/cleaved at the LTR polyadenylation site are shown below the Northern blot.