Abstract
The signal recognition particle (SRP) is a ribonucleoprotein consisting of six distinct polypeptide components and one molecule of small cytoplasmic RNA (7SL RNA). The particle was previously shown to function in protein translocation across and protein integration into the endoplasmic reticulum membrane. Homogeneous signal recognition particle preparations were visualized by electron microscopy (i) after negative staining, (ii) by dark-field imaging of unstained specimens, and (iii) by platinum-shadowing. The results of each of these different techniques indicate that the signal recognition particle is a rod-shaped particle 5-6 nm wide and 23-24 nm long.
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Selected References
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- Andrews D. W., Ottensmeyer F. P. Electron microscopy of the poly-L-lysine alpha-helix. Ultramicroscopy. 1982;9(4):337–348. doi: 10.1016/0304-3991(82)90094-8. [DOI] [PubMed] [Google Scholar]
- Bazett-Jones D. P., Ottensmeyer F. P. A model for the structure of nucleoprotamine. J Ultrastruct Res. 1979 Jun;67(3):255–266. doi: 10.1016/s0022-5320(79)80026-x. [DOI] [PubMed] [Google Scholar]
- Bernabeu C., Tobin E. M., Fowler A., Zabin I., Lake J. A. Nascent polypeptide chains exit the ribosome in the same relative position in both eucaryotes and procaryotes. J Cell Biol. 1983 May;96(5):1471–1474. doi: 10.1083/jcb.96.5.1471. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Gilmore R., Blobel G., Walter P. Protein translocation across the endoplasmic reticulum. I. Detection in the microsomal membrane of a receptor for the signal recognition particle. J Cell Biol. 1982 Nov;95(2 Pt 1):463–469. doi: 10.1083/jcb.95.2.463. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Lake J. A., Strycharz W. A. Ribosomal proteins L1, L17 and L27 from Escherichia coli localized at single sites on the large subunit by immune electron microscopy. J Mol Biol. 1981 Dec 25;153(4):979–992. doi: 10.1016/0022-2836(81)90462-9. [DOI] [PubMed] [Google Scholar]
- Meyer D. I., Krause E., Dobberstein B. Secretory protein translocation across membranes-the role of the "docking protein'. Nature. 1982 Jun 24;297(5868):647–650. doi: 10.1038/297647a0. [DOI] [PubMed] [Google Scholar]
- Ottensmeyer F. P., Bazett-Jones D. P., Hewitt J., Price G. B. Structure analysis of small proteins by electron microscopy: valinomycin, bacitracin and low molecular weight cell growth stimulators. Ultramicroscopy. 1978;3(3):303–313. doi: 10.1016/s0304-3991(78)80040-0. [DOI] [PubMed] [Google Scholar]
- Ottensmeyer F. P., Whiting R. F., Schmidt E. E., Clemens R. S. Electron microtephroscopy of proteins. A close look at the ashes of myokinase and protamine. J Ultrastruct Res. 1975 Aug;52(2):193–201. doi: 10.1016/s0022-5320(75)80111-0. [DOI] [PubMed] [Google Scholar]
- Wall J., Hainfeld J., Haschemeyer R. H., Mosesson M. W. Analysis of human fibrinogen by scanning transmission electron microscopy. Ann N Y Acad Sci. 1983 Jun 27;408:164–179. doi: 10.1111/j.1749-6632.1983.tb23243.x. [DOI] [PubMed] [Google Scholar]
- Walter P., Blobel G. Preparation of microsomal membranes for cotranslational protein translocation. Methods Enzymol. 1983;96:84–93. doi: 10.1016/s0076-6879(83)96010-x. [DOI] [PubMed] [Google Scholar]
- 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]
- Walter P., Blobel G. Signal recognition particle contains a 7S RNA essential for protein translocation across the endoplasmic reticulum. Nature. 1982 Oct 21;299(5885):691–698. doi: 10.1038/299691a0. [DOI] [PubMed] [Google Scholar]
- Walter P., Blobel G. Signal recognition particle: a ribonucleoprotein required for cotranslational translocation of proteins, isolation and properties. Methods Enzymol. 1983;96:682–691. doi: 10.1016/s0076-6879(83)96057-3. [DOI] [PubMed] [Google Scholar]
- Walter P., Blobel G. Translocation of proteins across the endoplasmic reticulum III. Signal recognition protein (SRP) causes signal sequence-dependent and site-specific arrest of chain elongation that is released by microsomal membranes. J Cell Biol. 1981 Nov;91(2 Pt 1):557–561. doi: 10.1083/jcb.91.2.557. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Walter P., Gilmore R., Blobel G. Protein translocation across the endoplasmic reticulum. Cell. 1984 Aug;38(1):5–8. doi: 10.1016/0092-8674(84)90520-8. [DOI] [PubMed] [Google Scholar]
- Walter P., Ibrahimi I., Blobel G. Translocation of proteins across the endoplasmic reticulum. I. Signal recognition protein (SRP) binds to in-vitro-assembled polysomes synthesizing secretory protein. J Cell Biol. 1981 Nov;91(2 Pt 1):545–550. doi: 10.1083/jcb.91.2.545. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Whiting R. F., Ottensmeyer F. P. Heavy atoms in model compounds and nucleic acid imaged by dark field transmission electron microscopy. J Mol Biol. 1972 Jun 20;67(2):173–181. doi: 10.1016/0022-2836(72)90234-3. [DOI] [PubMed] [Google Scholar]