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. 1988 Nov;7(11):3553–3557. doi: 10.1002/j.1460-2075.1988.tb03232.x

Signal recognition particle (SRP) stabilizes the translocation-competent conformation of pre-secretory proteins.

P Sanz 1, D I Meyer 1
PMCID: PMC454857  PMID: 2850167

Abstract

When affinity-purified proOmpA was diluted out of 8 M urea into a sample of yeast microsomes, it was translocated and processed in the absence of any cytosolic factors; an intact membrane and ATP were the only requirements. The translocation competence of proOmpA was lost, however, during a 15-h incubation at 0 degrees C. The competence was retained when trigger factor and a yeast cytosolic extract were present during incubations at 0 degrees C. The same reactions were carried out with affinity-purified prepro-alpha-factor, and the same results were obtained with the exception that trigger factor was not required. When the various cytosolic factors were replaced with SRP, the addition of yeast microsomes after 15 h resulted in the translocation and processing (and glycosylation) of both proOmpA and prepro-alpha-factor. Pancreatic microsomes were also used in this type of assay, and it was found that proOmpA (but not prepro-alpha-factor) could be translocated when diluted out of urea. In this case, as with yeast microsomes, translocation competence was maintained by SRP. These results show that in addition to a recognition and targeting function, SRP can stabilize the translocation-competent conformation of pre-secretory proteins in vitro for translocation across eukaryotic membranes.

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Selected References

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

  1. Ainger K. J., Meyer D. I. Translocation of nascent secretory proteins across membranes can occur late in translation. EMBO J. 1986 May;5(5):951–955. doi: 10.1002/j.1460-2075.1986.tb04308.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Chen W. J., Douglas M. G. The role of protein structure in the mitochondrial import pathway. Unfolding of mitochondrially bound precursors is required for membrane translocation. J Biol Chem. 1987 Nov 15;262(32):15605–15609. [PubMed] [Google Scholar]
  3. Chirico W. J., Waters M. G., Blobel G. 70K heat shock related proteins stimulate protein translocation into microsomes. Nature. 1988 Apr 28;332(6167):805–810. doi: 10.1038/332805a0. [DOI] [PubMed] [Google Scholar]
  4. Collier D. N., Bankaitis V. A., Weiss J. B., Bassford P. J., Jr The antifolding activity of SecB promotes the export of the E. coli maltose-binding protein. Cell. 1988 Apr 22;53(2):273–283. doi: 10.1016/0092-8674(88)90389-3. [DOI] [PubMed] [Google Scholar]
  5. Crooke E., Brundage L., Rice M., Wickner W. ProOmpA spontaneously folds in a membrane assembly competent state which trigger factor stabilizes. EMBO J. 1988 Jun;7(6):1831–1835. doi: 10.1002/j.1460-2075.1988.tb03015.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Crooke E., Wickner W. Trigger factor: a soluble protein that folds pro-OmpA into a membrane-assembly-competent form. Proc Natl Acad Sci U S A. 1987 Aug;84(15):5216–5220. doi: 10.1073/pnas.84.15.5216. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Deshaies R. J., Koch B. D., Werner-Washburne M., Craig E. A., Schekman R. A subfamily of stress proteins facilitates translocation of secretory and mitochondrial precursor polypeptides. Nature. 1988 Apr 28;332(6167):800–805. doi: 10.1038/332800a0. [DOI] [PubMed] [Google Scholar]
  8. Eilers M., Hwang S., Schatz G. Unfolding and refolding of a purified precursor protein during import into isolated mitochondria. EMBO J. 1988 Apr;7(4):1139–1145. doi: 10.1002/j.1460-2075.1988.tb02923.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Eilers M., Schatz G. Binding of a specific ligand inhibits import of a purified precursor protein into mitochondria. Nature. 1986 Jul 17;322(6076):228–232. doi: 10.1038/322228a0. [DOI] [PubMed] [Google Scholar]
  10. Garcia P. D., Walter P. Full-length prepro-alpha-factor can be translocated across the mammalian microsomal membrane only if translation has not terminated. J Cell Biol. 1988 Apr;106(4):1043–1048. doi: 10.1083/jcb.106.4.1043. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Hansen W., Garcia P. D., Walter P. In vitro protein translocation across the yeast endoplasmic reticulum: ATP-dependent posttranslational translocation of the prepro-alpha-factor. Cell. 1986 May 9;45(3):397–406. doi: 10.1016/0092-8674(86)90325-9. [DOI] [PubMed] [Google Scholar]
  12. Hansen W., Walter P. Prepro-carboxypeptidase Y and a truncated form of pre-invertase, but not full-length pre-invertase, can be posttranslationally translocated across microsomal vesicle membranes from Saccharomyces cerevisiae. J Cell Biol. 1988 Apr;106(4):1075–1081. doi: 10.1083/jcb.106.4.1075. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Hortsch M., Meyer D. I. Transfer of secretory proteins through the membrane of the endoplasmic reticulum. Int Rev Cytol. 1986;102:215–242. doi: 10.1016/s0074-7696(08)61276-0. [DOI] [PubMed] [Google Scholar]
  14. Krieg U. C., Walter P., Johnson A. E. Photocrosslinking of the signal sequence of nascent preprolactin to the 54-kilodalton polypeptide of the signal recognition particle. Proc Natl Acad Sci U S A. 1986 Nov;83(22):8604–8608. doi: 10.1073/pnas.83.22.8604. [DOI] [PMC free article] [PubMed] [Google Scholar]
  15. Kurzchalia T. V., Wiedmann M., Girshovich A. S., Bochkareva E. S., Bielka H., Rapoport T. A. The signal sequence of nascent preprolactin interacts with the 54K polypeptide of the signal recognition particle. Nature. 1986 Apr 17;320(6063):634–636. doi: 10.1038/320634a0. [DOI] [PubMed] [Google Scholar]
  16. Meyer D. I., Dobberstein B. A membrane component essential for vectorial translocation of nascent proteins across the endoplasmic reticulum: requirements for its extraction and reassociation with the membrane. J Cell Biol. 1980 Nov;87(2 Pt 1):498–502. doi: 10.1083/jcb.87.2.498. [DOI] [PMC free article] [PubMed] [Google Scholar]
  17. Müller G., Zimmermann R. Import of honeybee prepromelittin into the endoplasmic reticulum: structural basis for independence of SRP and docking protein. EMBO J. 1987 Jul;6(7):2099–2107. doi: 10.1002/j.1460-2075.1987.tb02476.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  18. Pelham H. R. Speculations on the functions of the major heat shock and glucose-regulated proteins. Cell. 1986 Sep 26;46(7):959–961. doi: 10.1016/0092-8674(86)90693-8. [DOI] [PubMed] [Google Scholar]
  19. Randall L. L., Hardy S. J. Correlation of competence for export with lack of tertiary structure of the mature species: a study in vivo of maltose-binding protein in E. coli. Cell. 1986 Sep 12;46(6):921–928. doi: 10.1016/0092-8674(86)90074-7. [DOI] [PubMed] [Google Scholar]
  20. Rothblatt J. A., Meyer D. I. Secretion in yeast: reconstitution of the translocation and glycosylation of alpha-factor and invertase in a homologous cell-free system. Cell. 1986 Feb 28;44(4):619–628. doi: 10.1016/0092-8674(86)90271-0. [DOI] [PubMed] [Google Scholar]
  21. Rothblatt J. A., Meyer D. I. Secretion in yeast: translocation and glycosylation of prepro-alpha-factor in vitro can occur via an ATP-dependent post-translational mechanism. EMBO J. 1986 May;5(5):1031–1036. doi: 10.1002/j.1460-2075.1986.tb04318.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  22. Rothblatt J. A., Webb J. R., Ammerer G., Meyer D. I. Secretion in yeast: structural features influencing the post-translational translocation of prepro-alpha-factor in vitro. EMBO J. 1987 Nov;6(11):3455–3463. doi: 10.1002/j.1460-2075.1987.tb02669.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  23. Rothman J. E., Kornberg R. D. Cell biology. An unfolding story of protein translocation. Nature. 1986 Jul 17;322(6076):209–210. doi: 10.1038/322209a0. [DOI] [PubMed] [Google Scholar]
  24. Schleyer M., Neupert W. Transport of proteins into mitochondria: translocational intermediates spanning contact sites between outer and inner membranes. Cell. 1985 Nov;43(1):339–350. doi: 10.1016/0092-8674(85)90039-x. [DOI] [PubMed] [Google Scholar]
  25. Siegel V., Walter P. The affinity of signal recognition particle for presecretory proteins is dependent on nascent chain length. EMBO J. 1988 Jun;7(6):1769–1775. doi: 10.1002/j.1460-2075.1988.tb03007.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  26. Walter P., Blobel G. Purification of a membrane-associated protein complex required for protein translocation across the endoplasmic reticulum. Proc Natl Acad Sci U S A. 1980 Dec;77(12):7112–7116. doi: 10.1073/pnas.77.12.7112. [DOI] [PMC free article] [PubMed] [Google Scholar]
  27. Walter P., Lingappa V. R. Mechanism of protein translocation across the endoplasmic reticulum membrane. Annu Rev Cell Biol. 1986;2:499–516. doi: 10.1146/annurev.cb.02.110186.002435. [DOI] [PubMed] [Google Scholar]
  28. Waters M. G., Blobel G. Secretory protein translocation in a yeast cell-free system can occur posttranslationally and requires ATP hydrolysis. J Cell Biol. 1986 May;102(5):1543–1550. doi: 10.1083/jcb.102.5.1543. [DOI] [PMC free article] [PubMed] [Google Scholar]
  29. Waters M. G., Chirico W. J., Blobel G. Protein translocation across the yeast microsomal membrane is stimulated by a soluble factor. J Cell Biol. 1986 Dec;103(6 Pt 2):2629–2636. doi: 10.1083/jcb.103.6.2629. [DOI] [PMC free article] [PubMed] [Google Scholar]
  30. Wickner W. The assembly of proteins into biological membranes: The membrane trigger hypothesis. Annu Rev Biochem. 1979;48:23–45. doi: 10.1146/annurev.bi.48.070179.000323. [DOI] [PubMed] [Google Scholar]
  31. Zimmermann R., Sagstetter M., Lewis M. J., Pelham H. R. Seventy-kilodalton heat shock proteins and an additional component from reticulocyte lysate stimulate import of M13 procoat protein into microsomes. EMBO J. 1988 Sep;7(9):2875–2880. doi: 10.1002/j.1460-2075.1988.tb03144.x. [DOI] [PMC free article] [PubMed] [Google Scholar]

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