RT-PCR of the mRNA for mutant TM del791-801 and wild type from the transiently transfected COS-7 cells.

Total RNA was reverse transcribed with random primers and the cDNA used as a template for PCR amplification with 2 TM primers flanking the deleted region. The size of the normal product is 143 bp (lane 4). The deletion gives rise to a smaller, 132-bp product (lane 2). Both transcripts were detected in cells cotransfected with both TM variants (wild-type and mutant, lane 6). The 100-bp marker (Life Technologies) was loaded in lane 1. Negative controls without reverse-transcriptase (lanes 3, 5, 7) or without template (lane 8) were included.