Colon carcinoma cells HT29 express a splice variant of DR3 missing the exon 6. A) Schematic representation of the normal splicing and the splicing associated with the loss of exon 6 within DR3v2. B) Predicted amino acids sequence of DR3v2 deleted of exon 6. The transmembrane domain is shown in the black box and the black line represents the death domain. Identical amino acid sequences are in black and non-identical are in red. GeneBank sequence NP_003781.1 was used as reference for DR3v2. C) Total RNA from different cell lines were extracted and were amplified by reverse transcriptase. Primers were designed to amplify by PCR the region from exon 5 to exon 7 of DR3v2. The resulting products were run through agarose gel. D) Total RNA from SW480 or SW620 cell lines were extracted and were amplified by reverse transcriptase. PCR reactions were carried out using specific primers amplifying region around exon 6 which produce a 97bp band for the DR3v2Δ6. Automated sizing and relative quantification of the amplicon versus total amplicons was performed using the manufacturer's software.