Reagent	Volume (ml)
Nuclease-free H2O	419.5
Tris-Cl, pH 7.8 (1 M)	30
Potassium chloride (1 M)	37.5
Magnesium chloride (1 M)	2.5
Nonidet P-40 (10%)	5
EDTA (0.5 M)	1.02
Polyadenylic acid, potassium salt (2 mg/ml)	1.25
Oligo-dT primer (25 μg/ml)	3.25
Total volume	500