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Proceedings of the National Academy of Sciences of the United States of America logoLink to Proceedings of the National Academy of Sciences of the United States of America
. 1976 Apr;73(4):1179–1183. doi: 10.1073/pnas.73.4.1179

mRNA-dependent synthesis of authentic precursor to human placental lactogen: conversion to its mature hormone form in ascites cell-free extracts.

E Szczesna, I Boime
PMCID: PMC430224  PMID: 1063399

Abstract

Messenger RNA derived from term placenta directs the synthesis of human placental lactogen (hPL, molecular weight 22,200) in an ascites 30,000 X g post-mitochondrial supernate (S-30). When the S-30 is fractionated into ribosome and cell-sap (S-100) fractions, and these are recombined for incubation, term placental mRNA directs the synthesis of a protein with a molecular weight of 25,000. This protein contains authentic hPL tryptic peptides. This suggested that during the separation of ribosomes and S-100 a component responsible for cleavage was lost. A 1.0 M sucrose cushion was used for the preparation of ribosomes and S-100 and membranous material accumulated at the sucrose interphase. When this membrane fraction was added back to the ribosome-S-100 system only hPl was formed. Cleavage was greatest when membranes were added within the first few minutes of incubation. In a run-off system composed of term polysomes, ascites S-100, and the inhibitor of initiation, pactamycin, the 25,000 molecular weight material, referred to as pre-hPL, was also synthesized. These data strongly suggest that (i) pre-hPL is an authentic percursor to hPL, (ii) cleavage of the precursor primarily occurs on nascent, ribosome-bound peptide chains, and (iii) pre-hPL is the primary gene product.

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Selected References

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  1. Bevan M. J. The vectorial release of nascent immunoglobulin peptides. Biochem J. 1971 Mar;122(1):5–11. doi: 10.1042/bj1220005. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Blobel G., Dobberstein B. Transfer of proteins across membranes. I. Presence of proteolytically processed and unprocessed nascent immunoglobulin light chains on membrane-bound ribosomes of murine myeloma. J Cell Biol. 1975 Dec;67(3):835–851. doi: 10.1083/jcb.67.3.835. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Boime I., Boguslawski S., Caine J. The translation of a human placental lactogen mRNA fraction in heterologous cell-free systems: the synthesis of a possible precursor. Biochem Biophys Res Commun. 1975 Jan 6;62(1):103–109. doi: 10.1016/s0006-291x(75)80411-6. [DOI] [PubMed] [Google Scholar]
  4. Boime I., Boguslawski S. The synthesis of human placental lactogen by ribosomes derived from human placenta. Proc Natl Acad Sci U S A. 1974 Apr;71(4):1322–1325. doi: 10.1073/pnas.71.4.1322. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Boime I., McWilliams D., Szczesna E., Camel M. Synthesis of human placental lactogen messenger RNA as a function of gestation. J Biol Chem. 1976 Feb 10;251(3):820–825. [PubMed] [Google Scholar]
  6. Butterworth B. E., Rueckert R. R. Gene order of encephalomyocarditis virus as determined by studies with pactamycin. J Virol. 1972 May;9(5):823–828. doi: 10.1128/jvi.9.5.823-828.1972. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Harrison T. M., Brownlee G. G., Milstein C. Studies on polysome-membrane interactions in mouse myeloma cells. Eur J Biochem. 1974 Sep 16;47(3):613–620. doi: 10.1111/j.1432-1033.1974.tb03733.x. [DOI] [PubMed] [Google Scholar]
  8. Jacobson M. F., Asso J., Baltimore D. Further evidence on the formation of poliovirus proteins. J Mol Biol. 1970 May 14;49(3):657–669. doi: 10.1016/0022-2836(70)90289-5. [DOI] [PubMed] [Google Scholar]
  9. Kemper B., Habener J. F., Mulligan R. C., Potts J. T., Jr, Rich A. Pre-proparathyroid hormone: a direct translation product of parathyroid messenger RNA. Proc Natl Acad Sci U S A. 1974 Sep;71(9):3731–3735. doi: 10.1073/pnas.71.9.3731. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. Lawrence C., Thach R. E. Identification of a viral protein involved in post-translational maturation of the encephalomyocarditis virus capsid precursor. J Virol. 1975 Apr;15(4):918–928. doi: 10.1128/jvi.15.4.918-928.1975. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Mach B., Faust C., Vassalli P. Purification of 14S messenger RNA of immunoglobulin light chain that codes for a possible light-chain precursor. Proc Natl Acad Sci U S A. 1973 Feb;70(2):451–455. doi: 10.1073/pnas.70.2.451. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. Milstein C., Brownlee G. G., Harrison T. M., Mathews M. B. A possible precursor of immunoglobulin light chains. Nat New Biol. 1972 Sep 27;239(91):117–120. doi: 10.1038/newbio239117a0. [DOI] [PubMed] [Google Scholar]
  13. Redman C. M., Siekevitz P., Palade G. E. Synthesis and transfer of amylase in pigeon pancreatic micromosomes. J Biol Chem. 1966 Mar 10;241(5):1150–1158. [PubMed] [Google Scholar]
  14. Roberts B. E., Paterson B. M. Efficient translation of tobacco mosaic virus RNA and rabbit globin 9S RNA in a cell-free system from commercial wheat germ. Proc Natl Acad Sci U S A. 1973 Aug;70(8):2330–2334. doi: 10.1073/pnas.70.8.2330. [DOI] [PMC free article] [PubMed] [Google Scholar]
  15. Sabatini D. D., Blobel G. Controlled proteolysis of nascent polypeptides in rat liver cell fractions. II. Location of the polypeptides in rough microsomes. J Cell Biol. 1970 Apr;45(1):146–157. doi: 10.1083/jcb.45.1.146. [DOI] [PMC free article] [PubMed] [Google Scholar]
  16. Schechter I. Biologically and chemically pure mRNA coding for a mouse immunoglobulin L-chain prepared with the aid of antibodies and immobilized oligothymidine. Proc Natl Acad Sci U S A. 1973 Aug;70(8):2256–2260. doi: 10.1073/pnas.70.8.2256. [DOI] [PMC free article] [PubMed] [Google Scholar]
  17. Sherwood L. M., Handwerger S., McLaurin W. D., Lanner M. Amino-acid sequence of human placental lactogen. Nat New Biol. 1971 Sep 8;233(36):59–61. doi: 10.1038/newbio233059a0. [DOI] [PubMed] [Google Scholar]
  18. Swan D., Aviv H., Leder P. Purification and properties of biologically active messenger RNA for a myeloma light chain. Proc Natl Acad Sci U S A. 1972 Jul;69(7):1967–1971. doi: 10.1073/pnas.69.7.1967. [DOI] [PMC free article] [PubMed] [Google Scholar]

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