Immunological characterization of secretory proteins of chromaffin granules: chromogranins A, chromogranins B, and enkephalin-containing peptides.
The soluble proteins of bovine chromaffin granules can be resolved into about 40 proteins by two-dimensional electrophoresis. Use of several antisera enabled us to characterize most of these proteins with the immune replica technique. An antiserum against dopamine beta-hydroxylase reacted with one protein of Mr 75,000. Met-enkephalin antisera labeled eight proteins of Mr 23,000-14,000. A new method was developed to obtain highly purified chromogranin A for immunization. The antiserum reacted with chromogranin A and several smaller proteins of similar pI. This specific antiserum did not react with a second family of hitherto undescribed proteins, which we propose to call chromogranins B. An antiserum against these proteins was raised. It labeled several proteins ranging in Mr from 100,000 to 24,000 and focusing at pH 5.2. Subcellular fractionation established that chromogranins B are specifically localized in chromaffin granules of several species. They are secreted from the adrenal medulla during cholinergic stimulation. We conclude that apart from dopamine beta-hydroxylase chromaffin granules contain three families of immunologically unrelated proteins.
D000313:Adrenal Medulla / Q000032:analysis; D000818:Animals; D002417:Cattle; D002837:Chromaffin Granules / Q000032:analysis*; D002838:Chromaffin System / Q000032:analysis*; D053379:Chromogranin A; D002864:Chromogranins / Q000032:analysis* / Q000276:immunology; D004299:Dopamine beta-Hydroxylase / Q000032:analysis; D004745:Enkephalins / Q000032:analysis*; D007106:Immune Sera / Q000276:immunology; D008970:Molecular Weight; D009419:Nerve Tissue Proteins / Q000032:analysis*; D010455:Peptides / Q000032:analysis
D053379:Chromogranin A; D002864:Chromogranins; D004745:Enkephalins; D007106:Immune Sera; D009419:Nerve Tissue Proteins; D010455:Peptides; D004299:Dopamine beta-Hydroxylase