Figure 8

An ASF/SF2-dependent ESE within exon 2. (A) Sequence of exon 2 (top line) and analyzed mutations. The heptameric sequences (M1 and M2) of the bipartite ESE are boxed and the mutations are given below exon 2 sequence. A schematic drawing of the two-intron minigene with exon 2 as internal exon flanked by A1 and D2 is given below the sequences. (B) HeLa-T4⁺ cells were transfected with LTR ds ex2 (ex2) or its mutations (cf. (A)), cotransfected with SVctat and pXGH5 (hGH) and analyzed by RT-PCR as described in Materials and Methods. (C) Pull-down analysis of in vitro transcripts of either exon 2 or exon 2 carrying both mutations, M1 and M2 in HeLa cell nuclear extract. The immunoblot was detected with a polyclonal SF2/ASF antibody.