Figure 5.

Effect of b₂a₂ antisense PNA on the level of bcr/abl mRNA in KYO-1 cells quantified by RT–PCR. The RNA from an equal number of PNA-untreated K562 (competitor) and PNA-treated KYO-1 cells was extracted. The extracted RNA was subjected to RT–PCR. Using primers EA122 and EA500, two amplified bcr/abl bands of 388 and 314 bp were obtained from K562 (b₃a₂ junction) and KYO-1 cells (b₂a₂ junction), respectively. When the KYO-1 cells were treated with asPNA or NLS-asPNA, the intensity of the 314 bp band, but not that of the 388 bp band, was reduced, compared to the band obtained by treating KYO-1 cells with scrPNA, a control PNA which is unable to bind to bcr/abl mRNA. As a control we also amplified a 128 bp DNA fragment of abl in each reaction tube, using primers ABL1A and EA500. As expected, this amplification is not influenced by PNA.