Human PDE1A (GenBank Accession No. NM_005019), full length with N-terminal GST tag, expressed in a Baculovirus infected Sf9 cell expression system. Specific Activity: 123 U/ug, 1 unit will lease 1nmole phosphate per minute from 400uM 5- AMP at 30C in a reaction buffer of 10mM Tris-HCl, pH 7.4, 0.2mM MgCl2. Assay Buffer: 10mM Tris-HCl, pH 7.4, 0.2mM MgCl2, 0.2mM CaCl2, and 240nM Calmodulin, 3, 5-cAMP substrate: 0.4mM, PDE1A: 1ng/ul. Applications: Useful for the study of enzyme kinetics, screening inhibitors, and selectivity profiling. Recommended Dilution: Optimal dilutions to be determined by the researcher. Storage and Stability: Aliquot to avoid repeated freezing and thawing and store at -70C. For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap. Aliquots are stable for at least 6 months.