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. 1979 Aug;76(8):3819–3823. doi: 10.1073/pnas.76.8.3819

Primary structure of the NH2-terminal extra piece of the precursor to human placental lactogen.

L M Sherwood, Y Burstein, I Schechter
PMCID: PMC383926  PMID: 291043

Abstract

The cell-free translation product of human placental lactogen mRNA is a precursor molecule larger than the mature hormone that circulates in plasma. To determine the structure of pre-placental lactogen, the poly(A)-rich RNA fraction of term placenta was isolated and translated in a wheat germ cell-free system. The mRNA programmed the synthesis of a major protein, 3000 daltons larger than placental lactogen, that was specifically precipitated by hormone antibodies. The immunoprecipitated protein was labeled separately with 20 radioactive amino acids and subjected to sequence analysis. The results showed the synthesis of pre-placental lactogen in which an extra piece 25 residues long preceded the NH2 terminus of the mature protein. The structure of the extra piece is as follows: Met-Pro-Gly-Ser-Arg-Thr-Ser-Leu-Leu-Ala-Phe-Ala-Leu-Leu-Cys-Leu-Pro-Trp-Leu-Gln-Glu-Ala-Gly-Ala-. Met1 is the initiator residue because only initiator [35S]Met-tRNAMet1, but not internal [35S]Met-tRNA2Met, donated NH2-terminal methionine. The structure of the extra piece showed little homology with that of unrelated hormones but striking homology (64%) with the extra piece of rat pre-growth hormone. Most amino acid substitutions involved a single base change in the codon. Mature human placental lactogen and rat growth hormone have 59% homology in sequence. Thus, our findings provide additional evidence to support the common evolutionary origin of these hormones, not only of the mature proteins but also of the extra piece segments.

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Selected References

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  1. Birken S., Smith D. L., Canfield R. E., Boime I. Partial amino acid sequence of human placental lactogen precursor and its mature hormone form produced by membrane-associated enzyme activity. Biochem Biophys Res Commun. 1977 Jan 10;74(1):106–112. doi: 10.1016/0006-291x(77)91381-x. [DOI] [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., 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]
  4. Burstein Y., Schechter I. Amino acid sequence of the NH2-terminal extra piece segments of the precursors of mouse immunoglobulin lambda1-type and kappa-type light chains. Proc Natl Acad Sci U S A. 1977 Feb;74(2):716–720. doi: 10.1073/pnas.74.2.716. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Burstein Y., Schechter I. Amino acid-sequence variability at the N-terminal extra piece of mouse immunoglobulin light-chain precursors of the same and different subgroups. Biochem J. 1976 Jul 1;157(1):145–151. doi: 10.1042/bj1570145. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Chan S. J., Keim P., Steiner D. F. Cell-free synthesis of rat preproinsulins: characterization and partial amino acid sequence determination. Proc Natl Acad Sci U S A. 1976 Jun;73(6):1964–1968. doi: 10.1073/pnas.73.6.1964. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Devillers-Thiery A., Kindt T., Scheele G., Blobel G. Homology in amino-terminal sequence of precursors to pancreatic secretory proteins. Proc Natl Acad Sci U S A. 1975 Dec;72(12):5016–5020. doi: 10.1073/pnas.72.12.5016. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. FRIESEN H. PURIFICATION OF A PLACENTAL FACTOR WITH IMMUNOLOGICAL AND CHEMICAL SIMILARITY TO HUMAN GROWTH HORMONE. Endocrinology. 1965 Mar;76:369–381. doi: 10.1210/endo-76-3-369. [DOI] [PubMed] [Google Scholar]
  9. Gorecki M., Zeelon E. P. Cell-free synthesis of rat parotid preamylase. J Biol Chem. 1979 Jan 25;254(2):525–529. [PubMed] [Google Scholar]
  10. Grumbach M. M., Kaplan S. L., Sciarra J. J., Burr I. M. Chorionic growth hormone-prolactin (CGP): secretion, disposition, biologic activity in man, and postulated function as the "growth hormone" of the 2d half of pregnancy. Ann N Y Acad Sci. 1968 Feb 5;148(2):501–531. doi: 10.1111/j.1749-6632.1968.tb20372.x. [DOI] [PubMed] [Google Scholar]
  11. Habener J. F., Rosenblatt M., Kemper B., Kronenberg H. M., Rich A., Potts J. T., Jr Pre-proparathyroid hormone; amino acid sequence, chemical synthesis, and some biological studies of the precursor region. Proc Natl Acad Sci U S A. 1978 Jun;75(6):2616–2620. doi: 10.1073/pnas.75.6.2616. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. JOSIMOVICH J. B., MACLAREN J. A. Presence in the human placenta and term serum of a highly lactogenic substance immunologically related to pituitary growth hormone. Endocrinology. 1962 Aug;71:209–220. doi: 10.1210/endo-71-2-209. [DOI] [PubMed] [Google Scholar]
  13. Li C. H., Dixon J. S., Chung D. Primary structure of the human chorionic somatomammotropin (HCS) molecule. Science. 1971 Jul 2;173(3991):56–58. doi: 10.1126/science.173.3991.56. [DOI] [PubMed] [Google Scholar]
  14. Lingappa V. R., Devillers-Thiery A., Blobel G. Nascent prehormones are intermediates in the biosynthesis of authentic bovine pituitary growth hormone and prolactin. Proc Natl Acad Sci U S A. 1977 Jun;74(6):2432–2436. doi: 10.1073/pnas.74.6.2432. [DOI] [PMC free article] [PubMed] [Google Scholar]
  15. Mains R. E., Eipper B. A., Ling N. Common precursor to corticotropins and endorphins. Proc Natl Acad Sci U S A. 1977 Jul;74(7):3014–3018. doi: 10.1073/pnas.74.7.3014. [DOI] [PMC free article] [PubMed] [Google Scholar]
  16. McKean D. J., Maurer R. A. Complete amino acid sequence of the precursor region of rat prolactin. Biochemistry. 1978 Nov 28;17(24):5215–5219. doi: 10.1021/bi00617a022. [DOI] [PubMed] [Google Scholar]
  17. Mercier J. C., Haze G., Gaye P., Hue D. Amino terminal sequence of the precursor of ovine beta-lactoglobulin. Biochem Biophys Res Commun. 1978 Jun 29;82(4):1236–1245. doi: 10.1016/0006-291x(78)90320-0. [DOI] [PubMed] [Google Scholar]
  18. Niall H. D., Hogan M. L., Sauer R., Rosenblum I. Y., Greenwood F. C. Sequences of pituitary and placental lactogenic and growth hormones: evolution from a primordial peptide by gene reduplication. Proc Natl Acad Sci U S A. 1971 Apr;68(4):866–870. doi: 10.1073/pnas.68.4.866. [DOI] [PMC free article] [PubMed] [Google Scholar]
  19. Niall H. D., Hogan M. L., Tregear G. W., Segre G. V., Hwang P., Friesen H. The chemistry of growth hormone and the lactogenic hormones. Recent Prog Horm Res. 1973;29:387–416. doi: 10.1016/b978-0-12-571129-6.50014-2. [DOI] [PubMed] [Google Scholar]
  20. 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]
  21. Schechter I., Burstein Y. Identification of N-terminal methionine in the precursor of immunoglobulin light chain. Initiation of translation of messenger ribonucleic acid in plants and animals. Biochem J. 1976 Mar 1;153(3):543–550. doi: 10.1042/bj1530543. [DOI] [PMC free article] [PubMed] [Google Scholar]
  22. Schechter I., Burstein Y. Marked hydrophobicity of the NH2-terminal extra piece of immunoglobulin light-chain precursors: possible physiological functions of the extra piece. Proc Natl Acad Sci U S A. 1976 Sep;73(9):3273–3277. doi: 10.1073/pnas.73.9.3273. [DOI] [PMC free article] [PubMed] [Google Scholar]
  23. Schechter I. Use of antibodies for the isolation of biologically pure messenger ribonucleic acid from fully functional eukaryotic cells. Biochemistry. 1974 Apr 23;13(9):1875–1885. doi: 10.1021/bi00706a016. [DOI] [PubMed] [Google Scholar]
  24. Seeburg P. H., Shine J., Martial J. A., Baxter J. D., Goodman H. M. Nucleotide sequence and amplification in bacteria of structural gene for rat growth hormone. Nature. 1977 Dec 8;270(5637):486–494. doi: 10.1038/270486a0. [DOI] [PubMed] [Google Scholar]
  25. Segrest J. P., Feldmann R. J. Membrane proteins: amino acid sequence and membrane penetration. J Mol Biol. 1974 Aug 25;87(4):853–858. doi: 10.1016/0022-2836(74)90090-4. [DOI] [PubMed] [Google Scholar]
  26. 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]
  27. Sherwood L. M. Human prolactin. N Engl J Med. 1971 Apr 8;284(14):774–777. doi: 10.1056/NEJM197104082841407. [DOI] [PubMed] [Google Scholar]
  28. Shine J., Seeburg P. H., Martial J. A., Baxter J. D., Goodman H. M. Construction and analysis of recombinant DNA for human chorionic somatomammotropin. Nature. 1977 Dec 8;270(5637):494–499. doi: 10.1038/270494a0. [DOI] [PubMed] [Google Scholar]
  29. Shome B., Parlow A. F. Human pituitary prolactin (hPRL): the entire linear amino acid sequence. J Clin Endocrinol Metab. 1977 Nov;45(5):1112–1115. doi: 10.1210/jcem-45-5-1112. [DOI] [PubMed] [Google Scholar]
  30. Smithies O., Gibson D., Fanning E. M., Goodfliesh R. M., Gilman J. G., Ballantyne D. L. Quantitative procedures for use with the Edman-Begg sequenator. Partial sequences of two unusual immunoglobulin light chains, Rzf and Sac. Biochemistry. 1971 Dec 21;10(26):4912–4921. doi: 10.1021/bi00802a013. [DOI] [PubMed] [Google Scholar]
  31. Strauss A. W., Bennett C. D., Donohue A. M., Rodkey J. A., Alberts A. W. Rat liver pre-proalbumin: complete amino acid sequence of the pre-piece. Analysis of the direct translation product of albumin messenger RNA. J Biol Chem. 1977 Oct 10;252(19):6846–6855. [PubMed] [Google Scholar]
  32. Sussman P. M., Tushinski R. J., Bancroft F. C. Pregrowth hormone: product of the translation in vitro of messenger RNA coding for growth hormone. Proc Natl Acad Sci U S A. 1976 Jan;73(1):29–33. doi: 10.1073/pnas.73.1.29. [DOI] [PMC free article] [PubMed] [Google Scholar]
  33. Szczesna E., Boime I. mRNA-dependent synthesis of authentic precursor to human placental lactogen: conversion to its mature hormone form in ascites cell-free extracts. Proc Natl Acad Sci U S A. 1976 Apr;73(4):1179–1183. doi: 10.1073/pnas.73.4.1179. [DOI] [PMC free article] [PubMed] [Google Scholar]
  34. Thibodeau S. N., Palmiter R. D., Walsh K. A. Precursor of egg white ovomucoid. Amino acid sequence of an NH2-terminal extension. J Biol Chem. 1978 Dec 25;253(24):9018–9023. [PubMed] [Google Scholar]
  35. Zemell R., Burstein Y., Schechter I. Initiator methionine residues at the NH2-termini of the two precursors of MOPC-41 immunoglobulin light chain. Studies with the initiator and internal tRNAMet species. Eur J Biochem. 1978 Aug 15;89(1):187–193. doi: 10.1111/j.1432-1033.1978.tb20911.x. [DOI] [PubMed] [Google Scholar]

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