PDE4B is a member of the type IV, cyclic AMP (cAMP)-specific, cyclic nucleotide phosphodiesterase (PDE) family. Enzymes of the cAMP-dependent phosphodiesterase type 4 (PDE4) family are important in hydrolyzing cAMP produced by G-protein coupled receptor (GPCR) stimulated adenylyl cyclases. Four genes (PDE4A, B, C and D) make up the PDE4 family. cAMP-dependent phosphodiesterase type B (PDE4B) family consists of four known splice variants, PDE4B1, B2, B3 and a novel 66kD PDE4B4 protein. One or more subtype variants of PDE4B are ubiquitously present in all mammalian cells. In CNS, all four PDE4B subtype variants are expressed in varying ratios and their activity is regulated in tandem with GPCRs stimulation. Some PDE4B variants are also substrate for PKA-dependent phosphorylation. Peripheral tissues exhibit differential expression of PDE4B1, B2 and B4 variants; the PDE4B4 (66kD protein) is the major PDE4B variant expressed in lungs, testis and heart. In testis PDE4B enzymes are expressed in somatic cells (Sertoli and Leydig cells) while PDE4A is localized in germ cells.
Source:Recombinant protein corresponding to full length human PDE4B2, fused with a N-terminal GST-Tag and C-terminal His-Tag, expressed in an Baculovirus infected Sf9 cell expression system.
Molecular Weight: 91.2kD
Specific Activity:Lot Specific. Sample Lot Value: 11,890pmol/min/ug
Unit Definition:1 unit is defined as the amount of enzyme that will convert 1 pmole of 3', 5'-cAMP to 5' AMP per min at 37°C.
Assay Conditions:10mM Tris-HCl, pH7.4, 10mM MgCl2, 1mM MnCl2, 200uM cAMP, 0.1ng/ul PDE4B2 at 37°C for 20min. Quantified by 5′-nucleotidase cleaving the 5′-AMP product and releasing the phosphate group which is detected by Malachite Green Reagent.
Application:Useful for the study of enzyme kinetics, screening inhibitors, and selectivity profiling. Other applications not tested.
Recommended Dilution: Optimal dilution determined by the researcher.
Storage and Stability:Aliquot to avoid repeated freezing and thawing and store at -70°C. 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.
