Fig. 1. Identification of the p53 mutation by insertion in the IGR-N-91 cell line. SH refers to SH-SY5Y cells; IGR refers to IGR-N-91 cells. (A) Western blot (left panel) of protein total lysates showing that the p53 protein band is of a higher molecular mass in IGR cells than in SH cells. Electrophoresis (right panel), in 2% agarose, of RTPCR products spanning exons 1-11, show an amplified fragment in IGR approximately 300 bp longer than in SH. (B) Restriction endonuclease fragments from StyI, RsaI and TaqI. (C) Polyacrylamide electrophoresis of exons 6-10 showing a higher band (300 bp) in IGR than in SH (left panel); when PCR was performed using the forward primer, spanning the end of exon 9 and the first four nucleotides at the beginning of exon 7, only IGR had an amplified fragment (right panel). (D) Schematic representing the restriction sites of each enzyme in B. Arrowhead, IGR amplified fragment.