Semi-quantitative reverse-transcription – PCR analysis of SAGE tags. Identity of the SAGE tags and the number of cycles used in the PCR are: 2, GAPDH, 21 cycles; 13441, high affinity cationic amino acid transporter, 36 cycles; 15463, purine nucleoside phosphorylase, 35 cycles; 25004, lamin B receptor, 36 cycles; 10596, histone H3.3, 33 cycles; 4, fatty acid binding protein, 21 cycles; 10, 28 kDa glutathione S-transferase, 23 cycles; 1885, similar to nuclear ribonucleoprotein K, 36 cycles; and 684, similar to nucleoside diphosphate kinase, 30 cycles.