Skip to main content
PMC home page
The Journal of Cell Biology logoLink to The Journal of Cell Biology
. 1971 Jul 1;50(1):187–200. doi: 10.1083/jcb.50.1.187

CONCOMITANT SYNTHESIS OF MEMBRANE PROTEIN AND EXPORTABLE PROTEIN OF THE SECRETORY GRANULE IN RAT PAROTID GLAND

Abraham Amsterdam 1, Michael Schramm 1, Itzhak Ohad 1, Yoram Salomon 1, Zvi Selinger 1
PMCID: PMC2108431  PMID: 5563444

Abstract

After enzyme secretion the membrane of the secretory granule, which had been fused to the cell membrane, was resorbed into the cell. Experiments were therefore carried out to test whether formation of new secretory granules involves reutilization of the resorbed membrane or synthesis of a new membrane, de novo, from amino acids. Incorporation of amino acids-14C into proteins of various cell fractions was measured in vivo, 30, 120, and. 300 min after labeling. At all times the specific radioactivity of the secretory granule membrane was about equal to that of the granule's exportable content. At 120 and 300 min the specific radioactivity of the granule membrane and of the granule content was much higher than that of any other subcellular fraction. It is therefore concluded that the protein of the membrane is synthesized de novo concomitantly with the exportable protein. The proteins of the granule membrane could be distinguished from those of the granule content by gel electrophoresis. All major bands were labeled proportionately to their staining intensity. The amino acid composition of the secretory granule membrane was markedly different from that of the granule's content and also from that of the mitochondrial membrane. The granule membrane showed a high proline content, 30 moles/100 moles amino acids. The analyses show that the radioactivity of the granule membrane is indeed inherent in its proteins and is not due to contamination by other fractions. The possibility is considered that the exportable protein leaves the endoplasmic reticulum already enveloped by the newly synthesized membrane.

Full Text

The Full Text of this article is available as a PDF (1.3 MB).

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Amsterdam A., Ohad I., Schramm M. Dynamic changes in the ultrastructure of the acinar cell of the rat parotid gland during the secretory cycle. J Cell Biol. 1969 Jun;41(3):753–773. doi: 10.1083/jcb.41.3.753. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. CERIOTTI G. Determination of nucleic acids in animal tissues. J Biol Chem. 1955 May;214(1):59–70. [PubMed] [Google Scholar]
  3. Dallner G., Bergstrand A., Nilsson R. Heterogeneity of rough-surfaced liver microsomal membranes of adult, phenobarbital-treated, and newborn rats. J Cell Biol. 1968 Aug;38(2):257–276. doi: 10.1083/jcb.38.2.257. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Dallner G., Siekevitz P., Palade G. E. Biogenesis of endoplasmic reticulum membranes. I. Structural and chemical differentiation in developing rat hepatocyte. J Cell Biol. 1966 Jul;30(1):73–96. doi: 10.1083/jcb.30.1.73. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Eytan G., Ohad I. Biogenesis of chloroplast membranes. VI. Cooperation between cytoplasmic and chloroplast ribosomes in the synthesis of photosynthetic lamellar proteins during the greening process in a mutant of Chlamydomonas reinhardi y-1. J Biol Chem. 1970 Sep 10;245(17):4297–4307. [PubMed] [Google Scholar]
  6. FAWCETT D. W. Physiologically significant specializations of the cell surface. Circulation. 1962 Nov;26:1105–1132. doi: 10.1161/01.cir.26.5.1105. [DOI] [PubMed] [Google Scholar]
  7. GREEN D. E., MII S., KOHOUT P. M. Studies on the terminal electron transport system. I. Succinic dehydrogenase. J Biol Chem. 1955 Dec;217(2):551–567. [PubMed] [Google Scholar]
  8. Glaumann H., Dallner G. Subfractionation of smooth microsomes from rat liver. J Cell Biol. 1970 Oct;47(1):34–48. doi: 10.1083/jcb.47.1.34. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. HOCHSTEIN P., ERNSTER L. ADP-ACTIVATED LIPID PEROXIDATION COUPLED TO THE TPNH OXIDASE SYSTEM OF MICROSOMES. Biochem Biophys Res Commun. 1963 Aug 14;12:388–394. doi: 10.1016/0006-291x(63)90111-6. [DOI] [PubMed] [Google Scholar]
  10. Jamieson J. D., Palade G. E. Intracellular transport of secretory proteins in the pancreatic exocrine cell. 3. Dissociation of intracellular transport from protein synthesis. J Cell Biol. 1968 Dec;39(3):580–588. doi: 10.1083/jcb.39.3.580. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Jamieson J. D., Palade G. E. Intracellular transport of secretory proteins in the pancreatic exocrine cell. I. Role of the peripheral elements of the Golgi complex. J Cell Biol. 1967 Aug;34(2):577–596. doi: 10.1083/jcb.34.2.577. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. Jamieson J. D., Palade G. E. Intracellular transport of secretory proteins in the pancreatic exocrine cell. II. Transport to condensing vacuoles and zymogen granules. J Cell Biol. 1967 Aug;34(2):597–615. doi: 10.1083/jcb.34.2.597. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Jamieson J. D., Palade G. E. Intracellular transport of secretory proteins in the pancreatic exocrine cell. IV. Metabolic requirements. J Cell Biol. 1968 Dec;39(3):589–603. doi: 10.1083/jcb.39.3.589. [DOI] [PMC free article] [PubMed] [Google Scholar]
  14. KARNOVSKY M. L. Metabolic basis of phagocytic activity. Physiol Rev. 1962 Jan;42:143–168. doi: 10.1152/physrev.1962.42.1.143. [DOI] [PubMed] [Google Scholar]
  15. LOWRY O. H., ROSEBROUGH N. J., FARR A. L., RANDALL R. J. Protein measurement with the Folin phenol reagent. J Biol Chem. 1951 Nov;193(1):265–275. [PubMed] [Google Scholar]
  16. LUFT J. H. Improvements in epoxy resin embedding methods. J Biophys Biochem Cytol. 1961 Feb;9:409–414. doi: 10.1083/jcb.9.2.409. [DOI] [PMC free article] [PubMed] [Google Scholar]
  17. Lacy P. E., Howell S. L., Young D. A., Fink C. J. New hypothesis of insulin secretion. Nature. 1968 Sep 14;219(5159):1177–1179. doi: 10.1038/2191177a0. [DOI] [PubMed] [Google Scholar]
  18. MORRIS A. J., DICKMAN S. R. Biosynthesis of ribonuclease in mouse pancreas. J Biol Chem. 1960 May;235:1404–1408. [PubMed] [Google Scholar]
  19. Mandel I. D., Thompson R. H., Jr, Ellison S. A. Studies on the mucoproteins of human parotid saliva. Arch Oral Biol. 1965 May-Jun;10(3):499–507. doi: 10.1016/0003-9969(65)90116-0. [DOI] [PubMed] [Google Scholar]
  20. Morimoto T., Tashiro Y., Matsuura S. Chase of newly synthesized proteins in guinea-pig pancreas with cycloheximide. Biochim Biophys Acta. 1967 May 30;138(3):631–633. doi: 10.1016/0005-2787(67)90567-9. [DOI] [PubMed] [Google Scholar]
  21. REYNOLDS E. S. The use of lead citrate at high pH as an electron-opaque stain in electron microscopy. J Cell Biol. 1963 Apr;17:208–212. doi: 10.1083/jcb.17.1.208. [DOI] [PMC free article] [PubMed] [Google Scholar]
  22. SCHRAMM M., DANON D. The mechanism of enzyme secretion by the cell. I. Storage of amylase in the zymogen granules of the rat-parotis gland. Biochim Biophys Acta. 1961 Jun 10;50:102–112. doi: 10.1016/0006-3002(61)91065-4. [DOI] [PubMed] [Google Scholar]
  23. SIEKEVITZ P., PALADE G. E. A cyto-chemical study on the pancreas of the guinea pig. III. In vivo incorporation of leucine-1-C14 into the proteins of cell fractions. J Biophys Biochem Cytol. 1958 Sep 25;4(5):557–566. doi: 10.1083/jcb.4.5.557. [DOI] [PMC free article] [PubMed] [Google Scholar]
  24. Simson J. V. Discharge and restitution of secretory material in the rat parotid gland in response to isoproterenol. Z Zellforsch Mikrosk Anat. 1969;101(2):175–191. doi: 10.1007/BF00335726. [DOI] [PubMed] [Google Scholar]
  25. Stoner C. D., Sirak H. D. Osmotically-induced alterations in volume and ultrastructure of mitochondria isolated from rat liver and bovine heart. J Cell Biol. 1969 Dec;43(3):521–538. doi: 10.1083/jcb.43.3.521. [DOI] [PMC free article] [PubMed] [Google Scholar]
  26. Takayama K., MacLennan D. H., Tzagoloff A., Stoner C. D. Studies on the electron transfer system. LXVII. Polyacrylamide gel electrophoresis of the mitochondrial electron transfer complexes. Arch Biochem Biophys. 1966 Apr;114(1):223–230. doi: 10.1016/0003-9861(66)90324-9. [DOI] [PubMed] [Google Scholar]
  27. Viveros O. H., Arqueros L., Kirshner N. Mechanism of secretion from the adrenal medulla. V. Retention of storage vesicle membranes following release of adrenaline. Mol Pharmacol. 1969 Jul;5(4):342–349. [PubMed] [Google Scholar]
  28. Widnell C. C., Unkeless J. C. Partial purification of a lipoprotein with 5'-nucleotidase activity from membranes of rat liver cells. Proc Natl Acad Sci U S A. 1968 Nov;61(3):1050–1057. doi: 10.1073/pnas.61.3.1050. [DOI] [PMC free article] [PubMed] [Google Scholar]

Articles from The Journal of Cell Biology are provided here courtesy of The Rockefeller University Press

RESOURCES