Fig. 2. The SAP130 contained in the TFTC is not involved in splicing. (A) A 500 µg aliquot of NE was immunodepleted with an anti-TAFII30 (ID TAFII30) antibody. Proteins were analysed by western blotting using the indicated antibodies. The efficiency of the anti-TAFII30 immunodepletion and that of the SAP130 depletion was calculated by using a Bio-Rad GS700 Imaging Densitometer. (B) The extracts tested in (A) were used for in vitro splicing assays with a short version of the adenovirus E1A gene, which is spliced only in the 13S mRNA. The pre-mRNA (Transcript) and the correctly spliced transcript (mRNA) are indicated. Where indicated, 100 ng of SR proteins and 150 ng of TFTC were added to the reactions. Res: control immunodepletion with protein G–Sepharose alone.