Figure 2.
Expression of transmembrane serine proteases and trypsinogens. Total mRNAs from several human cell lines (293T, embryonic kidney; Huh7, hepatoma; A431, epidermoid carcinoma; HT1080, fibrosarcoma; H292, lung carcinoma; and A549, lung carcinoma) shown in Figure 1 were prepared, and their cDNAs were synthesized from the same amounts of total RNA with an oligo(dT)18 primer. The transcript copies of the TMPRSS genes (A) and trypsinogen genes (B) were amplified by 45 cycles of PCR with primers specific for each gene, separated electrophoretically and stained. Posi.: 1 × 104 molecules of target cDNA was used as each positive control. Nega.: H2O.