Figure 3.

(A) The structural analysis of the ATM 5′new Δ mutant. Nomenclature of the enzymes and cleavage site intensities are as described in the legend to Figure 2. (B) A schematic diagram of this mutant. The inserted bases with respect to the ATM Δ sequence are underlined and in bold. The in vitro splicing analysis of this 5′new Δ RNA compared with the ATM Δ RNA is reported in (C). The activation of the novel internal 5′ss during ATM pseudoexon splicing is indicated as a box with vertical lines. The ATM 5′new Δ mutant sequence has also been transferred to the pcDNA3 eukaryotic expression vector and transiently transfected in Hep3B cells (D).