title: Peptide mapping of multiple forms of cyclic nucleotide phosphodiesterase.
abstract: Purified multiple forms of 3':5'-cyclic-nucleotide phosphodiesterase (EC 3.1.4.17) were analyzed using two-dimensional tryptic pep]tide mapping of radioiodinated peptides. Comparisons of peptide maps of rat liver insulin-sensitive phosphodiesterase (PDE) with rat brain calmodulin-sensitive PDE suggest that some peptides co-migrate (31-43% co-migration). However, except for a single peptide, bovine retinal rod outer segment PDE, peptide maps appear unrelated to the other two forms (7-12% co-migration). In contrast, peptide maps of a 36,000-dalton proteolysis product of calmodulin-sensitive PDE are highly related to the peptide maps of a rat brain calmodulin-sensitive holoenzyme (73% co-migration). These results suggest that the multiple PDE forms are distinct molecular entities.
mesh_terms: D015105:3',5'-Cyclic-AMP Phosphodiesterases / Q000378:metabolism; D000818:Animals; D001921:Brain / Q000201:enzymology; D002147:Calmodulin / Q000494:pharmacology; D004789:Enzyme Activation; D007328:Insulin / Q000494:pharmacology; D007527:Isoenzymes; D008099:Liver / Q000201:enzymology; D008970:Molecular Weight; D010446:Peptide Fragments / Q000032:analysis; D051381:Rats
chemical_list: D002147:Calmodulin; D007328:Insulin; D007527:Isoenzymes; D010446:Peptide Fragments; D015105:3',5'-Cyclic-AMP Phosphodiesterases