Sulfated secreted forms of bovine and porcine parathyroid chromogranin A (secretory protein-I).
Chromogranin A (secretory protein-I) is an acidic sulfated glycoprotein found in secretory granules of most endocrine and neuroendocrine cells. In the parathyroid it is co-stored and secreted with parathormone in response to hypocalcemia. Differences in post-translational modifications have been reported between chromogranin A from the bovine adrenal and porcine parathyroid glands. The former has been reported to be sulfated mainly on oligosaccharide residues and apparently includes a proteoglycan form, whereas the latter was previously reported to be tyrosine sulfated with little of the proteoglycan form present. Here we have directly compared 35SO4-labeled parathyroid chromogranin A from the pig and the cow to determine if these reported differences were tissue or species specific. We find that the chromogranin A secreted by the bovine gland contains a proteoglycan form, whereas that from the porcine gland does not. Moreover, chromogranin A of both species is primarily sulfated on oligosaccharide residues with little if any tyrosine sulfate detected. Differences were detected in the structure of sulfated O-linked oligosaccharides in bovine and porcine parathyroid chromogranin A.
Gorr
S U
SU
Department of Oral Health, University of Louisville, Kentucky 40292.
Hamilton
J W
JW
Cohn
D V
DV
D000818:Animals; D002417:Cattle; D053379:Chromogranin A; D002864:Chromogranins / Q000378:metabolism*; D004591:Electrophoresis, Polyacrylamide Gel; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D010280:Parathyroid Glands / Q000378:metabolism*; D011233:Precipitin Tests; D013045:Species Specificity; D013056:Spectrophotometry, Ultraviolet; D013464:Sulfuric Acids / Q000737:chemistry; D013552:Swine
D053379:Chromogranin A; D002864:Chromogranins; D013464:Sulfuric Acids