Summary
The role of the 30 S ribosomal protein S 21 in ribosome function, specifically in relation to the initiation of polypeptide synthesis, was studied. Reconstituted particles using 16 S RNA and all purified 30 S proteins, but omitting S21. The reconstituted particles ([-S 21] particles) sedimented at 30 S and contained all the 30 S proteins except S 21 in approximately the same concentration as control reconstituted particles ([Σ Si] particles). In several functional assays including AUG-directed fMet-tRNA binding, [-S 21] particles were only 33 to 44% as active as complete particles. The addition of pure S 21 to [-S 21] particles showed 2 to 3 fold stimulation in AUG-directed fMet-tRNA binding using purified initiation factors IF 1 and IF2, assayed either in the presence or absence of 50 S subunits. Maximum stimulation was observed when approximately 0.5 to 1.0 mole of S 21 per mole of [-S 21] particles were added. We conclude that, contrary to the report of van Duin et al. (1972), S 21 does not inhibit AUG-directed fMet-tRNA binding, and that S 21 is required for full activity of the ribosomes in the initiation of polypeptide synthesis. Thus, the results published by van Duin et al. cannot be taken to support the postulated heterogeneity of the ribosome population in vivo. Possible reasons for the discrepancy between our conclusion and that of van Duin et al. are discussed.
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Duin, J. van., Knippenberg, P.H. van., Dieben, M., Kurland, C.G.: Functional heterogeneity of the 30 S ribosomal subunit of Escherichia coli, II. Effect of S 21 on initiation. Molec. gen. Genet. 116, 181–191 (1972)
Held, W. A., Mizushima, S., Nomura, M.: Reconstitution of Escherichia coli 30 S ribosomal subunits from purified molecular components. J. biol. Chem. 248, 5720–5730 (1973)
Held, W. A., Nomura, M.: Functional homology between the 30 S ribosomal protein S 7 from E. coli K 12 and the S 7 from E. coli MRE 600. Molec. gen. Genet. 122, 11–14 (1973a)
Held, W. A., Nomura, M.: The rate-determining step in the reconstitution of 30 S ribosomal subunits from Escherichia coli. Biochemistry, 12, 3273–3281 (1973b)
Hershey, J. W. B., Remold-O'Donnell, E. Kolakofsky, D., Dewey, K. F., Thach, R. E.: Isolation and purification of initiation factors f 1 and f 2. In: Methods in enzymology, Vol. XX, part C, p. 235–247 (K. Moldaye and L. Grossman, eds.). New York: Academic Press 1971
Hershey, J. W. B., Thach, R. E.: Role of guanosine 5′-triphosphate in the initiation of peptide synthesis, I. Synthesis of formylmethionyl-puromycin. Proc. nat. Acad. Sci (Wash.) 57, 759–766 (1967)
Kaltschmidt, E., Wittmann, H.G.: Ribosomal proteins VII. Two-dimensional polyacrylamide gel electrophoresis for fingerprinting of ribosomal proteins. Analyt. Biochem. 36, 401–412 (1970)
Kurland, C. G.: Structure and function of the bacterial ribosome. Ann. Rev. Biochem. 41, 337–408 (1972)
Kurland, C. G., Voynow, P., Hardy, S. J. S., Randall, L., Lutter, L.: Physical and functional heterogeneity of E. coli ribosomes. Cold Spr. Harb. Symp. quant. Biol. 34, 17–24 (1969)
Lowry, O. H., Rosebrough, N. J., Farr, A. L., Randall, R. J.: Protein measurement with the folin phenol, reagent. J. biol. Chem. 193, 265–275 (1951)
Mizushima, S., Nomura, M.: Assembly mapping of 30 S ribosomal proteins from E. coli. Nature (Lond.) 226, 1214–1218 (1970)
Nashimoto, H., Held, W. Kaltschmidt, E. Nomura M. Structure and function of bacterial ribosomes. XII. Accumulation of 21 S particles by some cold-sensitive mutants of Escherichia coli. J. molec. Biol. 62, 121–138 (1971)
Nomura, M.; Bacterial ribosome. Bact. Rev., 34, 228–277 (1970)
Nomura, M.: Assembly of bacterial, ribosomes. Science 179, 864–873 (1973)
Nomura, M., Mizushima, S., Ozaki M., Traub, P., Lowry, C.V.: Structure and function of ribosomes and their molecular components. Cold Spr. Harb. Symp. quant. Biol. 34, 49–61 (1969)
Ozaki, M., Mizushima, S., Nomura, M.: Identification and functional characterization of the protein controlled by the streptomycin-resistant locus in E. coli. Nature (Lond.) 222, 333–339 (1969)
Petre, J., Bollen, A., Nokin, P., Grosjean, H.: The binding of Escherichia coli ribosomes to matrix bound messenger RNA. Biochimie 54 823–827 (1972)
Randall-Hazelbauer, L.L., Kurland, C.G.: Identification of three 30 S proteins contributing to the ribosomal A site. Molec. gen. Genet. 115, 234–242 (1972)
Schofield, P., Zamecnik, P. C.: Cupric ion catalysis in hydrolysis of aminoacyl-tRNA. Biochim. biophys. Acta (Amst.) 155, 410–416 (1958)
Scolnick, E. M., Caskey, C. T.: Peptide chain termination, V. The role of release factors in mRNA termination codon recognition. Proc. nat. Acad. Sci. (Wash.) 64, 1235–1241 (1969)
Traub, P., Hosokowa, K., Craven, G. R., Nomura, M.: Structure and function of E. coli ribosomes, IV. Isolation and characterization of functonally avtive ribosomal proteins. Proc. nat. Acad. Sci. (Wash.) 58, 2430–2436 (1967)
Traub, P., Mizushima, S., Lowry, C. V., Nomura, M.: Reconstitution, of ribosomes from subribosomal components. In: Methods in enzymology, vol. XX, part C, p. 391–407 (K. Moldave and L. Grossman, eds.). New York: Academic Press 1971
Traub, P., Nomura, M.: Structure and function of Escherichia coli ribosomes, I. Partial fractionation of the functionally active ribosomal proteins and reconstitution, of artificial subribosomal particles. J. molec. Biol. 34, 575–593 (1968)
Voynow, P., Kurland, C. G.: Stoichiometry of the 30 S ribosomal proteins of Escherichia coli. Biochemistry 10, 517–524 (1971)
Wittmann, H. G., Stöffler, G., Hindennach,J., Kurland, C. G., Randall-Hazelbauer, L., Birge, E. A., Nomura, M., Kaltschmidt, E., Mizushima, S., Traut, R. R., Bickle, T. A.: Correlation of 30 S ribosomal proteins of Escherichia coli isolated in different laboratories. Molec. gen. Genet. 111, 327–333 (1971)
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Held, W.A., Nomura, M. & Hershey, J.W.B. Ribosomal protein S21 is required for full activity in the initiation of protein synthesis. Molec. Gen. Genet. 128, 11–22 (1974). https://doi.org/10.1007/BF00267291
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DOI: https://doi.org/10.1007/BF00267291