Scanning mutagenesis of constitutive exon 2 and exon 3.

(A) Scanning mutations (black rectangles) in the TAF6 minigene were generated by PCR before transfection into HeLa. RNA was isolated and splice products were analysed by RT-PCR as in Figure 3. The percentage of exogenous TAF6δ mRNA produced by a given mutated construct are graphically shown (x-axis). (B) As in panel A, except that mutations were in exon 3. (P<0.05 = *; P<0.01 = **; P<0.001 = ***).