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. 1984 Dec 1;99(6):2223–2230. doi: 10.1083/jcb.99.6.2223

Sorting and secretion of adrenocorticotropin in a pituitary tumor cell line after perturbation of the level of a secretory granule-specific proteoglycan

PMCID: PMC2113560  PMID: 6094592

Abstract

A mouse anterior pituitary tumor cell line (AtT-20) that secretes adrenocorticotropin and beta endorphin sorts the proteins it transports to the surface into two exocytotic pathways. AtT-20 cells also synthesize a secretory granule-specific sulfated molecule and secrete it on stimulation (Moore, H.-P., B. Gumbiner, and R. B. Kelly, 1983, J. Cell Biol., 97:810-817). We show here that this molecule is sensitive to proteolysis and that the residual sulfated material co-migrates with a chondroitin sulfate standard on thin-layer electrophoresis. Furthermore, this sulfated molecule is completely sensitive to chondroitinase ABC digestion. Thus the secretory granule-specific sulfated molecule is a proteoglycan with chondroitin sulfate side chains. We examined the role of proteoglycans in the sorting and secretion of adrenocorticotropin in AtT-20 cells by severely decreasing the amount of this vesicle-specific proteoglycan in two ways. First, a xyloside was used to inhibit proteoglycan biosynthesis; second, a variant of the AtT-20 cell line was isolated that synthesized little of the sulfated proteoglycan. In neither case was the sorting or secretion of adrenocorticotropin detectably altered, suggesting that the proteoglycan is not required for these processes.

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Selected References

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  1. Anderson P., Slorach S. A., Uvnäs B. Sequential exocytosis of storage granules during antigen-induced histamine release from sensitized rat mast cells in vitro. An electron microscopic study. Acta Physiol Scand. 1973 Jul;88(3):359–372. doi: 10.1111/j.1748-1716.1973.tb05465.x. [DOI] [PubMed] [Google Scholar]
  2. Buckley K. M., Schweitzer E. S., Miljanich G. P., Clift-O'Grady L., Kushner P. D., Reichardt L. F., Kelly R. B. A synaptic vesicle antigen is restricted to the junctional region of the presynaptic plasma membrane. Proc Natl Acad Sci U S A. 1983 Dec;80(23):7342–7346. doi: 10.1073/pnas.80.23.7342. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Carlson S. S., Kelly R. B. A highly antigenic proteoglycan-like component of cholinergic synaptic vesicles. J Biol Chem. 1983 Sep 25;258(18):11082–11091. [PubMed] [Google Scholar]
  4. Edge A. S., Spiro R. G. Presence of sulfate in N-glycosidically linked carbohydrate units of calf thyroid plasma membrane glycoproteins. J Biol Chem. 1984 Apr 25;259(8):4710–4713. [PubMed] [Google Scholar]
  5. FURTH J., GADSEN E. L., UPTON A. C. ACTH secreting transplantable pituitary tumors. Proc Soc Exp Biol Med. 1953 Oct;84(1):253–254. doi: 10.3181/00379727-84-20607. [DOI] [PubMed] [Google Scholar]
  6. Giannattasio G., Zanini A., Rosa P., Meldolesi J., Margolis R. K., margolis R. U. Molecular organization of prolactin granules. III. Intracellular transport of sulfated glycosaminoglycans and glycoproteins of the bovine prolactin granule matrix. J Cell Biol. 1980 Jul;86(1):273–279. doi: 10.1083/jcb.86.1.273. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Gumbiner B., Kelly R. B. Secretory granules of an anterior pituitary cell line, AtT-20, contain only mature forms of corticotropin and beta-lipotropin. Proc Natl Acad Sci U S A. 1981 Jan;78(1):318–322. doi: 10.1073/pnas.78.1.318. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Gumbiner B., Kelly R. B. Two distinct intracellular pathways transport secretory and membrane glycoproteins to the surface of pituitary tumor cells. Cell. 1982 Jan;28(1):51–59. doi: 10.1016/0092-8674(82)90374-9. [DOI] [PubMed] [Google Scholar]
  9. Hager D. A., Burgess R. R. Elution of proteins from sodium dodecyl sulfate-polyacrylamide gels, removal of sodium dodecyl sulfate, and renaturation of enzymatic activity: results with sigma subunit of Escherichia coli RNA polymerase, wheat germ DNA topoisomerase, and other enzymes. Anal Biochem. 1980 Nov 15;109(1):76–86. doi: 10.1016/0003-2697(80)90013-5. [DOI] [PubMed] [Google Scholar]
  10. Hampson I. N., Gallagher J. T. Separation of radiolabelled glycosaminoglycan oligosaccharides by polyacrylamide-gel electrophoresis. Biochem J. 1984 Aug 1;221(3):697–705. doi: 10.1042/bj2210697. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Hoshina H., Hortin G., Boime I. Rat pro-opiomelanocortin contains sulfate. Science. 1982 Jul 2;217(4554):63–64. doi: 10.1126/science.6283633. [DOI] [PubMed] [Google Scholar]
  12. Kelly R. B., Buckley K. M., Burgess T. L., Carlson S. S., Caroni P., Hooper J. E., Katzen A., Moore H. P., Pfeffer S. R., Schroer T. A. Membrane traffic in neurons and peptide-secreting cells. Cold Spring Harb Symp Quant Biol. 1983;48(Pt 2):697–705. doi: 10.1101/sqb.1983.048.01.073. [DOI] [PubMed] [Google Scholar]
  13. Laemmli U. K. Cleavage of structural proteins during the assembly of the head of bacteriophage T4. Nature. 1970 Aug 15;227(5259):680–685. doi: 10.1038/227680a0. [DOI] [PubMed] [Google Scholar]
  14. Lohmander L. S., Hascall V. C., Caplan A. I. Effects of 4-methyl umbelliferyl-beta-D-xylopyranoside on chondrogenesis and proteoglycan synthesis in chick limb bud mesenchymal cell cultures. J Biol Chem. 1979 Oct 25;254(20):10551–10561. [PubMed] [Google Scholar]
  15. Margolis R. U., Margolis R. K. Isolation of chondroitin sulfate and glycopeptides from chromaffin granules of adrenal medulla. Biochem Pharmacol. 1973 Sep 1;22(17):2195–2197. doi: 10.1016/0006-2952(73)90118-4. [DOI] [PubMed] [Google Scholar]
  16. Moore H. P., Gumbiner B., Kelly R. B. A subclass of proteins and sulfated macromolecules secreted by AtT-20 (mouse pituitary tumor) cells is sorted with adrenocorticotropin into dense secretory granules. J Cell Biol. 1983 Sep;97(3):810–817. doi: 10.1083/jcb.97.3.810. [DOI] [PMC free article] [PubMed] [Google Scholar]
  17. Moore H. P., Walker M. D., Lee F., Kelly R. B. Expressing a human proinsulin cDNA in a mouse ACTH-secreting cell. Intracellular storage, proteolytic processing, and secretion on stimulation. Cell. 1983 Dec;35(2 Pt 1):531–538. doi: 10.1016/0092-8674(83)90187-3. [DOI] [PubMed] [Google Scholar]
  18. Reggio H. A., Palade G. E. Sulfated compounds in the zymogen granules of the guinea pig pancreas. J Cell Biol. 1978 May;77(2):288–314. doi: 10.1083/jcb.77.2.288. [DOI] [PMC free article] [PubMed] [Google Scholar]
  19. Reggio H., Dagorn J. C. Ionic interactions between bovine chymotrypsinogen A and chondroitin sulfate A.B.C.. A possible model for molecular aggregation in zymogen granules. J Cell Biol. 1978 Sep;78(3):951–957. doi: 10.1083/jcb.78.3.951. [DOI] [PMC free article] [PubMed] [Google Scholar]
  20. Roberts J. L., Phillips M., Rosa P. A., Herbert E. Steps involved in the processing of common precursor forms of adrenocorticotropin and endorphin in cultures of mouse pituitary cells. Biochemistry. 1978 Aug 22;17(17):3609–3618. doi: 10.1021/bi00610a030. [DOI] [PubMed] [Google Scholar]
  21. Rodén L., Smith R. Structure of the neutral trisaccharide of the chondroitin 4-sulfate-protein linkage region. J Biol Chem. 1966 Dec 25;241(24):5949–5954. [PubMed] [Google Scholar]
  22. Rosa P., Zanini A. Purification of a sulfated secretory protein from the adenohypophysis. Immunochemical evidence that similar macromolecules are present in other glands. Eur J Cell Biol. 1983 Jul;31(1):94–98. [PubMed] [Google Scholar]
  23. Schwartz N. B., Galligani L., Ho P. L., Dorfman A. Stimulation of synthesis of free chondroitin sulfate chains by beta-D-xylosides in cultured cells. Proc Natl Acad Sci U S A. 1974 Oct;71(10):4047–4051. doi: 10.1073/pnas.71.10.4047. [DOI] [PMC free article] [PubMed] [Google Scholar]
  24. Slaby F., Farquhar M. G. Characterization of rat somatotroph and mammotroph secretory granules. Presence of sulfated molecules. Mol Cell Endocrinol. 1980 Apr;18(1):33–48. doi: 10.1016/0303-7207(80)90005-2. [DOI] [PubMed] [Google Scholar]
  25. Stadler H., Dowe G. H. Identification of a heparan sulphate-containing proteoglycan as a specific core component of cholinergic synaptic vesicles from Torpedo marmorata. EMBO J. 1982;1(11):1381–1384. doi: 10.1002/j.1460-2075.1982.tb01326.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  26. Stevens R. L., Austen K. F. Effect of p-nitrophenyl-beta-D-xyloside on proteoglycan and glycosaminoglycan biosynthesis in rat serosal mast cell cultures. J Biol Chem. 1982 Jan 10;257(1):253–259. [PubMed] [Google Scholar]
  27. Stevens R. L., Razin E., Austen K. F., Hein A., Caulfield J. P., Seno N., Schmid K., Akiyama F. Synthesis of chondroitin sulfate E glycosaminoglycan onto p-nitrophenyl-beta-D-xyloside and its localization to the secretory granules of rat serosal mast cells and mouse bone marrow-derived mast cells. J Biol Chem. 1983 May 10;258(9):5977–5984. [PubMed] [Google Scholar]
  28. Tartakoff A., Greene L. J., Palade G. E. Studies on the guinea pig pancreas. Fractionation and partial characterization of exocrine proteins. J Biol Chem. 1974 Dec 10;249(23):7420–7431. [PubMed] [Google Scholar]
  29. Zanini A., Giannattasio G., Nussdorfer G., Margolis R. K., Margolis R. U., Meldolesi J. Molecular organization of prolactin granules. II. Characterization of glycosaminoglycans and glycoproteins of the bovine prolactin matrix. J Cell Biol. 1980 Jul;86(1):260–272. doi: 10.1083/jcb.86.1.260. [DOI] [PMC free article] [PubMed] [Google Scholar]

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