Cyclic AMP phosphodiesterase in the migratory locust. Distribution and cytological localization

In Locusta migratoria a cyclic AMP-specific phosphodiesterase (PDE) was found in the following tissues: flight muscles, leg muscles, gonads, fat body, Malpighian tubules, and midgut. In all tissues the enzyme is present in a soluble and a structure-bound form. The relative activities of these two forms are characteristic for each tissue. The intracellular localization of the enzyme in muscle was studied by differential centrifugation. It was found to be present only in the fraction which sedimented at 1500 g and in the 105,000 g supernatant. In the 1500 g pellet PDE seems to be strongly associated with the contractile proteins. No cAMP was hydrolysed by the mitochondrial and microsomal fraction.