3 ,5 -Cyclic nucleotide phosphodiesterase assay

Huang, W., Zhang, Y., and Sportsman, J.R., A fluorescence polarization assay for cyclic nucleotide phosphodiesterases, /. Biomol. Screen., 7, 215, 2002. 

A polyacrylamide-boronate affinity gel, Affi-gel 601 , has been used for the separation of cyclic adenosine monophosphate, cyclic guanosine monophosphate, and cyclic cytidine monophosphate from their corresponding 5-nucleotides and nucleosides. A simple direct assay of 3 5 -cyclic nucleotide phosphodiesterase activity has been developed, based on the use of the gel. 

Quantitative analysis of cyclic nucleotides in protein kinase activity can also be performed using the FAB-MIKES technique. It gives results comparable with those obtained by conventional radiometric assay for monitoring the kinetics of cyclic nucleotide phosphodiesterase activity. 

Two of the seven cyclic nucleotide phosphodiesterase gene families PDE3 and PDE4, have a high affinity of cAMP and are specifically inhibited by ci-lostamide and rolipram, respectively. Using these inhibitors in assays with 0.1 [ H]cAMP as substrate, Gao et al. (1996) found PDE3 activity... 

By using highly specific radioactive cyclic nucleotides and the snake venom nucleotidase, the most sensitive, specific and convenient method of assay for phosphodiesterase has been evolved. 

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