For cDNA synthesis 1 µg of RNA was heat-treated at 70°C for 10 min and added to the following 20 µl reaction mix: 25 mM MgCl2, 4 µl; 10× reverse transcription buffer, 2 µl; 10 mM dNTP mixture, 2 µl; recombinant RNasin, 0.75 µl; random primers, 0.5 µl.