Taq storage buffer: 20 mM Tris-HCl, pH 8.0 @ 25 °C, 100 mM KCl, 0.1
mM Na2EDTA, 1 mM DTT, 0.5% (v/v) Tween 20, 0.5% (v/v) Nonidet-P40 and
50% (v/v) glycerol.

WPRE (Woodchuck
Posttranscriptional Regulatory Element) from the woodchuck hepatitis
virus, increases transgene expression.  cPPT (central Polypurine
Tract) from the HIV-1 integrase gene, increases the copy number of
lentivirus integrating into the host genome, thus increasing viral
titer. WPRE and cPPT together produce at least a four-fold increase in
protein expression in most cell types, compared to other vectors that
do not contain these elements.