Measurement of the potential activity of the type-1 and type-2 protein phosphatases in the crude tissue extract.
Although activation and conversion of the inactive/latent high-molecular-weight phosphatases to the Mr = approximately 35,000 catalytic subunits can be achieved by several procedures including freezing/thawing in 0.2 M 2-mercaptoethanol and digestion by proteolytic enzymes, strong indications have been obtained that they are distinct stimulating processes. For instance, when pig brain extracts were treated with trypsin, the type-1 phosphatase could be stimulated approximately 40 fold while the type-2 phosphatase was not slightly modified. Conversely, when the same crude extracts were treated with freezing/thawing in 2-mercaptoethanol, the type-2 phosphatase could be stimulated approximately 10 fold but surprisingly the type-1 species was not slightly influenced. It is suggested that hormonal study on the activity changes of the type-1 and type-2 phosphatase in a crude extract can be made possible by the selective using of these two triggers.
D000818:Animals; D001921:Brain / Q000201:enzymology; D004789:Enzyme Activation; D005615:Freezing; D008623:Mercaptoethanol / Q000494:pharmacology; D008970:Molecular Weight; D010749:Phosphoprotein Phosphatases / Q000145:classification / Q000302:isolation & purification*; D013552:Swine; D014020:Tissue Extracts / Q000032:analysis*; D014357:Trypsin / Q000494:pharmacology
D014020:Tissue Extracts; D008623:Mercaptoethanol; D010749:Phosphoprotein Phosphatases; D014357:Trypsin