FIG. 4.

RT-PCR detection of lasX and lasY transcripts. The approximate positions of the primers used (see Table 2) are indicated at the top. The reactions were performed with L45-2.1 RNA and primers 5566 (first-strand cDNA synthesis and PCR) and 6371 (lanes 1 and 2) or primers 4614 (first-strand cDNA and PCR) and 5751 (lanes 3 and 4). As a control of RNA-dependent amplification, RT was omitted from the samples run in lanes 2 and 4. The 5566-6371 and 4614-5751 PCR products with pCIM1 DNA as a template were run as molecular size controls in lanes 5 and 6, respectively.