scholarly journals Transgenic Mice Harboring Murine Luteinizing Hormone Receptor Promoter/β-Galactosidase Fusion Genes: Different Structural and Hormonal Requirements of Expression in the Testis, Ovary, and Adrenal Gland

Endocrinology ◽  
2002 ◽  
Vol 143 (10) ◽  
pp. 4096-4103 ◽  
Author(s):  
Tuula Hämäläinen ◽  
Jukka Kero ◽  
Matti Poutanen ◽  
Ilpo Huhtaniemi
Keyword(s):  
Adrenal Gland ◽  
Reporter Gene ◽  
Chorionic Gonadotropin ◽  
Human Chorionic Gonadotropin ◽  
Elevated Serum ◽  
Luteinizing Hormone Receptor ◽  
Fusion Genes ◽  
Β Subunit ◽  
Terminal Fragment ◽  
Serum Lh

Abstract In vivo regulation of the LH receptor (LHR) promoter was studied using transgenic (TG) mice harboring fusion genes containing three different lengths of the LHR promoter (7.4 kb, 2.1 kb, and 173 bp), fused with coding sequence of the Escherichia coli β-galactosidase (β-GAL) reporter gene. The length of the LHR promoter significantly affected the pattern of β-GAL expression. In the testis the shortest promoter directed expression primarily of the full-length β-GAL mRNA, but mainly truncated messages were transcribed from the longer LHR promoter/β-GAL constructs. The case was reversed in the ovary and adrenal gland. Furthermore, we have recently detected strong LHR expression in the adrenal gland of female mice with chronically elevated serum LH. Therefore, the regulation of the adrenal LHR expression was addressed in the present study using the LHR/β-GAL TG mice. Elevated LH levels were achieved in the LHR/β-GAL mice either by gonadectomy or cross-breeding them with TG mice overexpressing a chimeric protein of bovine LH β-subunit and the C-terminal fragment of human chorionic gonadotropin-β. In both models, β-GAL mRNA was found in the adrenal cortex when the 7.4-kb LHR promoter was applied but not in mice carrying the 173-bp LHR promoter. The 7.4-kb construct was activated also in the ovaries in the double TG LHR(β-GAL)/bovine LH β-subunit/C-terminal fragment of human chorionic gonadotropin-βmice in some theca-interstitial cells surrounding the follicles. Hence, the LHR promoter elements essential for directing β-GAL expression to the adrenal gland and ovary (7.4 kb) are different from those recently shown to be essential for the testicular expression (173 bp). In conclusion, elevated serum LH concentrations were found seminal for the LHR promoter activation in the ovaries and adrenals, and different lengths of the promoter are responsible for reporter gene expression in the testis, ovary, and adrenal gland.

Production of human chorionic gonadotropin—β subunit associated with an osteolytic meningioma

2002 ◽  
Vol 97 (1) ◽  
pp. 197-199 ◽  
Author(s):  
Cheng-shyuan Rau ◽  
Jui-wei Lin ◽  
Cheng-loong Liang ◽  
Tao-chen Lee ◽  
Han-jung Chen ◽  
...  
Keyword(s):  
Chorionic Gonadotropin ◽  
Human Chorionic Gonadotropin ◽  
Elevated Serum ◽  
Immunohistochemical Analysis ◽  
Serum Levels ◽  
Β Subunit ◽  
Content Type ◽  
First Case ◽  
Β Hcg ◽  
Microscopy Examination

✓ An osteolytic meningioma in a 36-year-old woman was accompanied by elevated serum levels of human chorionic gonadotropin—β subunit (β-HCG), which returned to normal after removal of the tumor. Light microscopy examination demonstrated a transitional meningioma. Immunohistochemical analysis revealed that the tumor cells had a positive reaction for β-HCG. This case illustrates the possibility that meningioma may be associated with clinically detectable secretion of β-HCG. To the authors' knowledge, this is the first case in which meningioma has been shown to secrete β-HCG. The authors believe that meningioma should be considered in the differential diagnosis of choriocarcinoma, embryonal cell tumor, germinoma, and metastatic ovarian tumor associated with elevated levels of β-HCG.

scholarly journals Translational Fusion of Two β-Subunits of Human Chorionic Gonadotropin Results in Production of a Novel Antagonist of the Hormone

Endocrinology ◽  
2007 ◽  
Vol 148 (8) ◽  
pp. 3977-3986 ◽  
Author(s):  
Satarupa Roy ◽  
Sunita Setlur ◽  
Rupali A. Gadkari ◽  
H. N. Krishnamurthy ◽  
Rajan R. Dighe
Keyword(s):  
Chorionic Gonadotropin ◽  
Human Chorionic Gonadotropin ◽  
Expression System ◽  
Biologically Active ◽  
Chain Molecule ◽  
Dependent Manner ◽  
Β Subunit ◽  
Single Chain ◽  
Α Subunit ◽  
Lh Receptor

The strategy of translationally fusing the α- and β-subunits of human chorionic gonadotropin (hCG) into a single-chain molecule has been used to produce novel analogs of hCG. Previously we reported expression of a biologically active single-chain analog hCGαβ expressed using Pichia expression system. Using the same expression system, another analog, in which the α-subunit was replaced with the second β-subunit, was expressed (hCGββ) and purified. hCGββ could bind to LH receptor with an affinity three times lower than that of hCG but failed to elicit any response. However, it could inhibit response to the hormone in vitro in a dose-dependent manner. Furthermore, it inhibited response to hCG in vivo indicating the antagonistic nature of the analog. However, it was unable to inhibit human FSH binding or response to human FSH, indicating the specificity of the effect. Characterization of hCGαβ and hCGββ using immunological tools showed alterations in the conformation of some of the epitopes, whereas others were unaltered. Unlike hCG, hCGββ interacts with two LH receptor molecules. These studies demonstrate that the presence of the second β-subunit in the single-chain molecule generated a structure that can be recognized by the receptor. However, due to the absence of α-subunit, the molecule is unable to elicit response. The strategy of fusing two β-subunits of glycoprotein hormones can be used to produce antagonists of these hormones.

Effect of peptide nicking in the human chorionic gonadotropin β-subunit on stimulation of recombinant human thyroid-stimulating hormone receptors

1994 ◽  
Vol 130 (1) ◽  
pp. 92-96 ◽  
Author(s):  
Masayoshi Yoshimura ◽  
A Eugene Pekary ◽  
Xuan-Ping Pang ◽  
Loretta Berg ◽  
Laurence A Cole ◽  
...  
Keyword(s):  
Los Angeles ◽  
Chorionic Gonadotropin ◽  
Human Chorionic Gonadotropin ◽  
Hormone Receptors ◽  
Thyroid Stimulating Hormone ◽  
Human Thyroid ◽  
Β Subunit ◽  
Trophoblastic Diseases ◽  
Thyrotropic Activity ◽  
Stimulating Hormone

Yoshimura M, Pekary AE, Pang X-P, Berg L, Cole LA, Kardana A, Hershman JM. Effect of peptide nicking in the human chorionic gonadotropin β-subunit on stimulation of recombinant human thyroid-stimulating hormone receptors. Eur J Endocrinol 1994;130:92–6. ISSN 0804–4643 It is now generally accepted that human chorionic gonadotropin (hCG) has thyroid-stimulating activity. Heterologous forms of the hCG molecule occur in the purified preparations extracted from urine of pregnant women and patients with trophoblastic diseases. This work was undertaken to determine the effect of peptide nicking in the hCG-β subunit on its thyrotropic potency. Using Chinese hamster ovary cells expressing functional human thyroid-stimulating hormone (TSH) receptors, we examined the effect of nicked hCG on cyclic AMP (cAMP) production and receptor binding. The effect of human leukocyte elastase (hLE), a nicking enzyme, on standard hCG also was examined in the cAMP assay and on receptor binding. We studied five hCG preparations extracted from the urine of normal pregnancy (CR-127 and P8) and trophoblastic diseases (C2, C5 and M4). Two preparations (C2, 96% nicked and M4, 100% nicked in the β44–49 region) showed about a 1.5-fold potency of standard hCG CR-127, which is also 20% nicked in the same region. Non-nicked hCG (P8) had the weakest potency among all of the samples tested. Treatment of standard hCG with hLE increased the cAMP response about two-fold. Dose-dependent displacement of bovine [125I]TSH by standard hCG and hLE-digested hCG was observed and was almost identical. We have confirmed the increased in vitro thyrotropic activity of hCG nicked in the β-intercysteine loop on recombinant human TSH receptors. These data suggest that peptide heterogeneity of the hCG molecule may modulate the in vivo thyrotropic activity of hCG in pregnant women and patients with trophoblastic diseases. Jerome M Hershman, Endocrinology-W111D, West Los Angeles VA Medical Center, Los Angeles, California 90073, USA

Structural and Functional Studies of the Tryptic Core of the Human Chorionic Gonadotropin β-Subunit*

Endocrinology ◽  
1987 ◽  
Vol 121 (2) ◽  
pp. 657-666 ◽  
Author(s):  
STEVEN BIRKEN ◽  
MARY ANN GAWINOWICZ KOLKS ◽  
SANIA AMR ◽  
BRUCE NISULA ◽  
DAVID PUETT
Keyword(s):  
Chorionic Gonadotropin ◽  
Human Chorionic Gonadotropin ◽  
Β Subunit ◽  
Functional Studies

Occurrence of Fragmentation of Free and Combined Forms of the β-Subunit of Human Chorionic Gonadotropin*

Endocrinology ◽  
1990 ◽  
Vol 126 (2) ◽  
pp. 687-694 ◽  
Author(s):  
ALAIN PUISIEUX ◽  
DOMINIQUE BELLET ◽  
FREDERIC TROALEN ◽  
ALAIN RAZAFINDRATSITA ◽  
CATHERINE LHOMME ◽  
...  
Keyword(s):  
Chorionic Gonadotropin ◽  
Human Chorionic Gonadotropin ◽  
Β Subunit
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