Figure 1

The existence of Tgfbr1 transcript variants in pleural effusion-derived tumor cells. Panel A: RT-PCR. Total RNA was extracted from WI38, HUVEC, and pleural effusion-derived tumor cells followed by reverse transcription. Nested PCR reactions amplified Tgfbr1 coding sequences using two pairs of primers, P1 and P2, as indicated at the top of Panel C. The resultant amplicons were resolved in a 1% agarose gel followed by gel purification, gene cloning, and direct sequencing. The nucleotide sequences flanking the truncated region(s) in each variant are marked at the top of Panel B. Panel C: Schematic illustration of the Tgfbr1 variants. DM1 and DM2 are in-frame variants lacking nucleotides 16–75 and 15–80, respectively, located in the signal sequence of the Tgfbr1 gene. DM3 and DM4 represent cytoplasmic variants lacking transmembrane and partial intracellular domains, as indicated.