RT–PCR amplification
of COT mRNAs in various mammals. RT of total liver RNA from mouse,
cow (bovine), pig, human, rat and Cos7 (monkey) cultured cells was
performed. The primers used were from the bovine COT cDNA: bE2.f
(5′-TGCATGGTACCATAAAATGGAAAATCAACTGGC-3′) and bE5.r (5′-CGGAATTGATTCATATCTAGAGGAGTATTTCC-3′) except for the rat cDNA which was
amplified with homologous rat primers E2.f (5′-TTTTCTTACTGTGACTATACCATGG-3′) and E5.r (5′-GGTTCATGTCTAGAGGAG-3′). The bands were sequenced and correspond
to cis-splicing at 493 (in rat) and 478 bp (in other
mammals), and trans-splicing (629 and 754 bp) only
in rat. The small difference in size of cis-spliced
bands among rat and other mammals is due to the differences in the
primers used.