|
|
|
|||||||
|
|||||||||
(Received for publication, May 12, 1997, and in revised form, June 10, 1997)
From the Laboratory of Molecular Endocrinology, Department of
Medicine, University of Maryland School of Medicine and the Institute
of Human Virology, Medical Biotechnology Center, Baltimore, Maryland
21201 and § NHLBI, National Institutes of Health,
Bethesda, Maryland 20892
The human thyroid-stimulating hormone (hTSH)
subunits
Volume 272, Number 34,
Issue of August 22, 1997
pp. 21312-21316
©1997 by The American Society for Biochemistry and Molecular Biology, Inc.
and 
are transcribed from different genes and associate
noncovalently to form the bioactive hTSH heterodimer. Dimerization is
rate-limiting for hTSH secretion, and dissociation leads to hormone
inactivation. Previous studies on human chorionic gonadotropin (hCG)
and human follicle-stimulating hormone had shown that it was possible
by subunit gene fusion to produce a bioactive, single chain hormone. However, neither the stability nor the clearance from the circulation of such fused glycoprotein hormones has been studied. We show here that
genetic fusion of the hTSH - and -subunits using the carboxyl-terminal peptide of the hCG -subunit as a linker created unimolecular hTSH whose receptor binding and bioactivity were comparable to native hTSH. Interestingly, the fused hTSH had higher thermostability and a longer plasma half-life than either native or
dimeric hTSH containing the hCG -subunit-carboxyl-terminal peptide,
suggesting that dimer dissociation may contribute to glycoprotein
hormone inactivation in vivo. In addition, we show for the
first time that synthesis of hTSH as a single polypeptide chain could
overcome certain mutagenesis-induced defects in hTSH secretion,
therefore enabling functional studies of such mutants. Thus, in
addition to prolongation of plasma half-life, genetic fusion of hTSH
subunits should be particularly relevant for the engineering of novel
analogs where desirable features are offset by decreased dimer
formation or stability. Such methods provide a general approach to
expand the spectrum of novel recombinant glycoprotein hormones
available for in vitro and in vivo study.
CiteULike 
Complore 
Connotea 
Del.icio.us 
Digg 
Reddit 
Technorati What's this?
This article has been cited by other articles:
|
|
 |
|
  S. Legardinier, J.-C. Poirier, D. Klett, Y. Combarnous, and C. Cahoreau Stability and biological activities of heterodimeric and single-chain equine LH/chorionic gonadotropin variants J. Mol. Endocrinol., April 1, 2008; 40(4): 185 - 198. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 E. P Lemke, B. M Adams, A. Jablonka-Shariff, I. Boime, and T. E Adams Single-chain human gonadotropin analogs induce follicle development in sheep J. Endocrinol., March 1, 2008; 196(3): 593 - 600. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 N. Azzam, R. Bar-Shalom, Z. Kraiem, and F. Fares Human Thyrotropin (TSH) Variants Designed by Site-Directed Mutagenesis Block TSH Activity in Vitro and in Vivo Endocrinology, June 1, 2005; 146(6): 2845 - 2850. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 V. Garcia-Campayo, A. Jablonka-Shariff, and I. Boime A Single-chain Bifunctional Gonadotropin Analog Is Secreted from Chinese Hamster Ovary Cells as Two Distinct Bioactive Species J. Biol. Chem., October 22, 2004; 279(43): 44286 - 44293. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 P. Narayan, J. Gray, and D. Puett Yoked Complexes of Human Choriogonadotropin and the Lutropin Receptor: Evidence that Monomeric Individual Subunits Are Inactive Mol. Endocrinol., December 1, 2002; 16(12): 2733 - 2745. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
V. Garcia-Campayo, T. R. Kumar, and I. Boime Thyrotropin, Follitropin, and Chorionic Gonadotropin Expressed as a Single Multifunctional Unit Reveal Remarkable Permissiveness in Receptor-Ligand Interactions Endocrinology, October 1, 2002; 143(10): 3773 - 3778. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
V. Garcia-Campayo and I. Boime Independent Activities of FSH and LH Structurally Confined in a Single Polypeptide: Selective Modification of the Relative Potencies of the Hormones Endocrinology, December 1, 2001; 142(12): 5203 - 5211. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 H. S. Seo, Y. J. Koo, J. Y. Lim, J. T. Song, C. H. Kim, J. K. Kim, J. S. Lee, and Y. D. Choi Characterization of a Bifunctional Enzyme Fusion of Trehalose-6-Phosphate Synthetase and Trehalose-6-Phosphate Phosphatase of Escherichia coli Appl. Envir. Microbiol., June 1, 2000; 66(6): 2484 - 2490. [Abstract] [Full Text]
|
|
|
|
|
|
P. Narayan, J. Gray, and D. Puett A Biologically Active Single Chain Human Chorionic Gonadotropin Analog with Altered Receptor Binding Properties Endocrinology, January 1, 2000; 141(1): 67 - 71. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. Kanda, A. Jablonka-Shariff, A. Sato, M. R. Pixley, E. Bos, T. Hiro’oka, D. Ben-Menahem, and I. Boime Genetic Fusion of an {alpha}-Subunit Gene to the Follicle-Stimulating Hormone and Chorionic Gonadotropin-{beta} Subunit Genes: Production of a Bifunctional Protein Mol. Endocrinol., November 1, 1999; 13(11): 1873 - 1881. [Abstract] [Full Text]
|
|
|
|
|
|
F. A. Fares, F. Levi, A. Z. Reznick, and Z. Kraiem Engineering a Potential Antagonist of Human Thyrotropin and Thyroid-stimulating Antibody J. Biol. Chem., February 9, 2001; 276(7): 4543 - 4548. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
D. Ben-Menahem, A. Jablonka-Shariff, R. K. Hyde, M. R. Pixley, S. Srivastava, P. Berger, and I. Boime The Position of the alpha and beta Subunits in a Single Chain Variant of Human Chorionic Gonadotropin Affects the Heterodimeric Interaction of the Subunits and Receptor-binding Epitopes J. Biol. Chem., August 3, 2001; 276(32): 29871 - 29879. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| All ASBMB Journals | Molecular and Cellular Proteomics |
| Journal of Lipid Research | ASBMB Today |