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Richard Ivell - One of the best experts on this subject based on the ideXlab platform.
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Identification of Markers for Precursor and Leydig Cell Differentiation in the Adult Rat Testis Following Ethane Dimethyl Sulphonate Administration1
2016Co-Authors: Katja J. Teerds, Marga Balvers, M. De Boer-brouwer, Jennifer H. Dorrington, Richard IvellAbstract:Administration of ethane dimethane sulphonate (EDS) to adult rats results in the destruction of all Leydig cells, followed by a complete regeneration. We investigated this regeneration process in more detail, using different markers for precursor and developing Leydig cells: the LH receptor, 3b-hydroxysteroid de-hydrogenase (3b-HSD), transforming growth Factor a (TGFa), and a new marker for Leydig cell maturation, Relaxin-Like Factor (RLF). LH receptor immunoreactivity was found in Leydig cell-de-pleted testes at 3 and 8 days after EDS administration. The pos-itive (precursor) cells had a mesenchymal-Like morphology. The number of LH receptor-positive cells 8 days after EDS adminis-tration was 15 6 4 per 500 Sertoli cell nuclei. Fifteen days after EDS administration, the first new Leydig cells could be observed. These cells stained positively with both the antibodies against the LH receptor and 3b-HSD, while some cells also stained pos-itively for TGFa. After EDS administration, RLF mRNA disappeared from the testis and reappeared again at the time of the appearance of the first Leydig cells. Concomitant with the increase in the number of Leydig cells, the number of RLF-expressing cells increased. The observations of the present study give further support to the hypothesis that Leydig cell development in the prepubertal testis, and in the adult testis following EDS administration, takes place along the same cell lineage and suggest, therefore, that the adult EDS-treated rat can serve as a model for studying the adult-type Leydig cell development that normally occurs in the prepubertal rat testis
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Reproductive biology of the Relaxin-Like Factor (RLF/INSL3). Biol Reprod 2002; 67:699–705
2016Co-Authors: Richard Ivell, Ross A D BathgateAbstract:The Relaxin-Like Factor (RLF), which is the product of the in-sulin-Like Factor 3 (INSL3) gene, is a new circulating peptide hormone of the Relaxin-insulin family. In male mammals, it is a major secretory product of the testicular Leydig cells, where it appears to be expressed constitutively but in a differentiation-dependent manner. In the adult testis, RLF expression is a good marker for fully differentiated adult-type Leydig cells, but it is only weakly expressed in prepubertal immature Leydig cells or in Leydig cells that have become hypertrophic or transformed. It is also an important product of the fetal Leydig cell popula-tion, where it has been demonstrated using knockout mice to be responsible for the second phase of testicular descent acting on the gubernaculum. INSL3 knockout mice are cryptorchid, and in estrogen-induced cryptorchidism, RLF levels in the testis are significantly reduced. RLF is also made in female tissues, particularly in the follicular theca cells of small antral follicles and in the corpus luteum of the cycle and pregnancy. The ru-minant ovary has a very high level of RLF expression, and anal-ysis of primary cultures of ovarian theca-lutein cells indicated that, as in the testis, expression is probably constitutive but dif-ferentiation dependent. Female INSL3 knockout mice have al-tered estrous cycles, where RLF may be involved in follicle se-lection, an idea strongly supported by observations on bovine secondary follicles. Recently, a novel 7-transmembrane domain receptor (LGR8 or Great) has been tentatively identified as the RLF receptor, and its deletion in mice leads also to cryptorchi-dism. follicular development, Leydig cells, Relaxin, theca cell
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Molecular Human Reproduction vol.5 no.2 pp. 104–108, 1999 Expression of Relaxin-Like Factor is down-regulated in human testicular Leydig cell neoplasia
2013Co-Authors: Thomas Klonisch, Martin Bergmann, Bernd Fischer, Richard Ivell, Marga Balvers, Sabine Kliesch, Klaus StegerAbstract:4To whom correspondence should be addressed In addition to their role in steroidogenesis in the male, testicular Leydig cells constitutively express large amounts of the peptide Relaxin-Like Factor (RLF), also known as Ley-IL. The Leydig cell-derived RLF belongs to the insulin-Like superfamily, which also includes Relaxin, insulin and the insulin-Like growth Factors, and within the testis is a specific marker of Leydig cells. Little information is available either on the regulation of gene expression or on the function of this Leydig cell-derived peptide. In the present study we have investigated the expression pattern of human RLF in patients with rare Leydig cell hyperplasia and adenoma. The expression of both mRNA and protein appear to be decreased in hyperplastic Leydig cells, whereas in the Leydig cell adenomas studied, large central areas of the adenoma were devoid of RLF mRNA and protein. Only Leydig cells located at the periphery of the adenoma displayed expression of RLF, with full agreement between in-situ hybridization and immunohistochemistry. It thus appears that the expression of the RLF gene and its products are down-regulated in Leydig cell hyperplasia and adenoma, consistent with a concomitant dedifferentiation of these cells. Key words: adenoma/human testis/hyperplasia/Leydig cell/Relaxin-Like facto
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DOI: 10.1093/molehr/gag025 The molecular basis of cryptorchidism*
2013Co-Authors: Richard Ivell, Stefan HartungAbstract:Cryptorchidism is the commonest malady to affect newborn male infants. Until recently, the molecular aetiology of this syndrome was unclear. Cryptorchidism may be part of a broader testicular dysgenesis syndrome, wherein a disturbance in steroid hormone metabolism, possibly through a perturbed hypothalamic±pituitary±gonadal axis could be involved. Disturbance may be genetic, or extrinsic through endocrine disruptors. Recently, the role of insulin-Like Factor-3 (INSL3; alternatively called Relaxin-Like Factor) has been highlighted through the cryptorchid phenotype of mice where genes for either INSL3 or its receptor have been ablated. INSL3 is produced by Leydig cells of the fetal testis and acts upon the gubernacular ligament to retain the gonad in the inguinal region, from which it later passes into the scrotum. INSL3 expression in fetal testis is inhibited by maternal exposure to estrogens. Although to date no mutations have been found in the human INSL3 gene responsible for cryptorchidism, one causative mutation in the INSL3 receptor (LGR8 or GREAT) has been reported. Studies on developmental transcription Factors, such as Hoxa-10 in mice, suggest that other speci®c molecular cascades could also lead to a cryptorchid phenotype. Considering its frequency in newborn children, and the severity of the untreated condition (infertility and often testicular cancer) these new ®ndings should generate new information on possible causes and treatments. Key words: cryptorchidism/Hoxa-10/INSL3/RLF/steroids/testicular dysgenesis syndrom
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Differentiation-specific action of orphan nuclear receptor NR5A1 (SF-1): transcriptional regulation in luteinizing bovine theca cells
Reproductive Biology and Endocrinology, 2006Co-Authors: Norbert Walther, Martina Jansen, Wasima Akbary, Richard IvellAbstract:Background The orphan nuclear receptor NR5A1 (steroidogenic Factor-1, SF-1) is a master regulator of tissue-specific gene expression in reproductive and steroidogenic tissues. Two activating functions, AF-1 and AF-2, have been described to function in a cooperative manner to recruit transcriptional coactivators to the promoter regions of NR5A1-controlled genes. Methods The role of the NR5A1 activating functions AF-1 and AF-2 was studied in primary bovine theca cells. Bovine theca cells were infected with recombinant adenovirus vectors over-expressing wild-type NR5A1 or NR5A1 mutants, in which one of the activating functions of this orphan nuclear receptor had been impaired. Under different culture conditions, theca cell-specific transcript levels were measured by reverse transcription and real-time PCR. Results Under culture conditions optimized for cell growth, transcriptional up-regulation of CYP11A1 (P450 side chain-cleavage enzyme) and INSL3 (Insulin-Like Factor 3, Relaxin-Like Factor (RLF)) was found to be dependent on the presence of NR5A1 carrying an intact AF-2. Under conditions inducing luteal differentiation of theca cells, CYP11A1 and STAR (Steroidogenic acute regulatory protein) were up-regulated by the action of luteinizing hormone (LH), whereas the differentiation-specific up-regulation of INSL3 was suppressed by LH in luteinizing theca cells. Inhibition of insulin- or IGF1- (insulin-Like growth Factor I) dependent signal transduction by the RAF1 kinase inhibitor GW5074 and the mitogen-activated protein kinase kinase inhibitor PD98059 resulted in the finding that RAF1 kinase inhibition was able to counteract the LH-dependent regulation of NR5A1-controlled genes, whereas inhibition of the mitogen-activated protein kinase (MAP kinase) pathway did not have any significant effect. Conclusion The regulation of the three NR5A1-controlled genes CYPA11, STAR, and INSL3 in luteinizing theca cells apparently is not dependent on NR5A1 activating functions AF-1 or AF-2. Activation of AF-1 here even appears to have an impairing effect on NR5A1 transcriptional activity, implying that up-regulation of NR5A1-controlled genes uses a different pathway. Our results might be explained by the possible existence of an interconnection between the RAF1 kinase and the cyclic AMP-protein kinase A pathway. Such a non-classical regulatory pathway might play an important role in the control of gene expression in reproductive and steroidogenic tissues.
Christian Schwabe - One of the best experts on this subject based on the ideXlab platform.
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Replacement of disulfides by amide bonds in the Relaxin-Like Factor (RLF/INSL3) reveals a role for the A11-B10 link in transmembrane signaling.
Biochemistry, 2012Co-Authors: Erika E Bullesbach, Christian SchwabeAbstract:The Relaxin-Like Factor (RLF) also named insulin-Like 3 (INSL3) consists of two polypeptide chains linked by two interchain and one intrachain disulfide bond. RLF binds to its receptor (LGR8 also n...
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replacement of disulfides by amide bonds in the Relaxin Like Factor rlf insl3 reveals a role for the a11 b10 link in transmembrane signaling
Biochemistry, 2012Co-Authors: Erika E Bullesbach, Christian SchwabeAbstract:The Relaxin-Like Factor (RLF) also named insulin-Like 3 (INSL3) consists of two polypeptide chains linked by two interchain and one intrachain disulfide bond. RLF binds to its receptor (LGR8 also n...
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Replacement of Disulfides by Amide Bonds in the Relaxin-Like Factor (RLF/INSL3) Reveals a Role for the A11–B10 Link in Transmembrane Signaling
2012Co-Authors: Erika E. Büllesbach, Christian SchwabeAbstract:The Relaxin-Like Factor (RLF) also named insulin-Like 3 (INSL3) consists of two polypeptide chains linked by two interchain and one intrachain disulfide bond. RLF binds to its receptor (LGR8 also named RXFP2) through the B chain and initiates transmembrane communication by activating the adenylate cyclase through the N-terminal region of both chains. Cystine A11–B10 occupies a unique position on the molecular surface just outside the binding region and between the two signaling ports. We have synthesized an RLF analogue in which the disulfide A11–B10 was replaced by a peptide bond and found that cAMP production ceased while receptor binding was not affected. In contrast, replacing the disulfide A24–B22 by a peptide bond reduced potency proportional to the binding affinity and lowered efficacy to 65%, while replacing disulfide A10–A15 by a peptide bond reduced binding affinity to 32% and lowered potency to 7% but maintained 100% efficacy. The exceptional properties of the derivative bearing an A11–B10 isopeptide cross-link suggests that the disulfide has a special role in signal transduction. We propose that disulfide A11–B10 serves as an insulator between the two ports, whereas the amide functionality disturbs the signal transmission complex Likely due to changes in polarity. The clear separation between receptor binding and signal activation sites within this small protein permits one to study how the Relaxin-Like Factor initiates the signal on the receptor that induces intracellular cAMP production
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The "hot wires" of the Relaxin-Like Factor (Insl3).
Annals of the New York Academy of Sciences, 2009Co-Authors: Christian Schwabe, Erika E BullesbachAbstract:The discovery of the total separation of receptor-binding and signal-generating regions of the Relaxin-Like Factor (RLF) has provided an opportunity to investigate the mechanism of transmembrane signaling. The receptor-binding residues of RLF are in the B chain of the two-chain molecule and extend from the midregion of the central helix to the tryptophan in position B27. The signal initiation site resides in two residues before the N-terminal cysteine in each chain. For optimal signaling the RLF requires five L-alpha-amino acids preceding cysteine A10, whereas the B chain requires only three. The nature of the side chains of these amino acids is not critical for the signaling function. Heuristic arguments lead us to suggest that the peptide bond is the signal-generating feature of RLF and possibly of other peptide hormones.
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Solution Structure of a Conformationally Restricted Fully Active Derivative of the Human Relaxin-Like Factor
Biochemistry, 2008Co-Authors: Erika E Bullesbach, Christian Schwabe, Mathias A. S. Hass, Malene Ringkjøbing Jensen, D.f. Hansen, Søren M. Kristensen, Jj LedAbstract:Analogous to insulin, the Relaxin-Like Factor (RLF) must undergo a structural transition to the active form prior to receptor binding. Thus, the C-terminus of the B chain of RLF folds toward the surface of the central B chain helix, causing partial obliteration of the two essential RLF receptor-binding site residues, valine B19 and tryptophan B27. Via comparison of the solution structure of a fully active C-terminally cross-linked RLF analogue with the native synthetic human RLF (hRLF), it became clear that the cross-linked analogue largely retains the essential folding of the native protein. Both proteins exist in a major and minor conformation, as revealed by multiple resonances from tryptophan B27 and adjacent residues on the B chain helix. Notably, the minor conformation is significantly more highly populated in the chemically cross-linked RLF than it is in the hRLF. In addition, compared to the unmodified molecule, subtle differences are observed within the B chain helix whereby the cross-linked derivative shows a reduced level of hydrogen bonding and significant peak broadening at the binding site residue ValB19. On the basis of these observations, we suggest that the solution structure of the native hormone represents an inactive conformer and that a dynamic equilibrium exists between the C-terminally unfolded binding conformation and the inactive conformation of the RLF.
Erika E Bullesbach - One of the best experts on this subject based on the ideXlab platform.
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Replacement of disulfides by amide bonds in the Relaxin-Like Factor (RLF/INSL3) reveals a role for the A11-B10 link in transmembrane signaling.
Biochemistry, 2012Co-Authors: Erika E Bullesbach, Christian SchwabeAbstract:The Relaxin-Like Factor (RLF) also named insulin-Like 3 (INSL3) consists of two polypeptide chains linked by two interchain and one intrachain disulfide bond. RLF binds to its receptor (LGR8 also n...
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replacement of disulfides by amide bonds in the Relaxin Like Factor rlf insl3 reveals a role for the a11 b10 link in transmembrane signaling
Biochemistry, 2012Co-Authors: Erika E Bullesbach, Christian SchwabeAbstract:The Relaxin-Like Factor (RLF) also named insulin-Like 3 (INSL3) consists of two polypeptide chains linked by two interchain and one intrachain disulfide bond. RLF binds to its receptor (LGR8 also n...
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Changes in plasma concentrations of insulin-Like peptide 3 and testosterone from birth to pubertal age in beef bulls.
Theriogenology, 2011Co-Authors: Noritoshi Kawate, Erika E Bullesbach, A. Ohnari, I.n. Pathirana, Mitsuhiro Sakase, Masahiro Takahashi, Toshio Inaba, Hiromichi TamadaAbstract:The objectives were to: (1) develop an enzyme immunoassay (EIA) for insulin-Like peptide 3 (INSL3) or Relaxin-Like Factor (RLF) in bovine plasma; (2) investigate changes of plasma INSL3 concentrations from birth to pubertal age of beef bulls; and (3) compare changes in plasma concentrations of INSL3, testosterone, and LH. Plasma samples were collected from beef bull calves (n = 15) at birth (0 d) and at 28, 56, and 84 d after birth. Furthermore, in beef bulls around pubertal age (n = 26; age range 3 to 22 mo), plasma samples were collected at 1 to 4 mo intervals. Plasma INSL3 concentrations increased (P < 0.05) from 0 to 28, 28 to 56, and from 56 to 84 d of age. Plasma testosterone concentrations increased (P < 0.001) from 0 to 28 d, and from 28 to 56 d, but did not change from 56 to 84 d. For bulls around pubertal age, plasma INSL3 concentrations did not change from the prepubertal phase (3 to 6 mo) to the early pubertal phase (6 to 12 mo), but increased (P < 0.05) from the early to late pubertal phases (12 to 18 mo), and from the late pubertal to postpubertal phases (18 to 22 mo). Plasma testosterone concentrations increased from the prepubertal to early pubertal phases (P < 0.001), but did not change thereafter. Plasma LH concentrations did not change from 0 d to 84 d, but decreased (P < 0.001) from prepubertal to early pubertal phase, with no significant change thereafter. Plasma INSL3 concentrations increased during the first 3 mo of life and throughout the pubertal age in beef bulls. There were similar dynamic patterns for INSL3 and testosterone during the first 3 mo of life, but patterns subsequently diverged in bulls around pubertal ages.
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The "hot wires" of the Relaxin-Like Factor (Insl3).
Annals of the New York Academy of Sciences, 2009Co-Authors: Christian Schwabe, Erika E BullesbachAbstract:The discovery of the total separation of receptor-binding and signal-generating regions of the Relaxin-Like Factor (RLF) has provided an opportunity to investigate the mechanism of transmembrane signaling. The receptor-binding residues of RLF are in the B chain of the two-chain molecule and extend from the midregion of the central helix to the tryptophan in position B27. The signal initiation site resides in two residues before the N-terminal cysteine in each chain. For optimal signaling the RLF requires five L-alpha-amino acids preceding cysteine A10, whereas the B chain requires only three. The nature of the side chains of these amino acids is not critical for the signaling function. Heuristic arguments lead us to suggest that the peptide bond is the signal-generating feature of RLF and possibly of other peptide hormones.
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Solution Structure of a Conformationally Restricted Fully Active Derivative of the Human Relaxin-Like Factor
Biochemistry, 2008Co-Authors: Erika E Bullesbach, Christian Schwabe, Mathias A. S. Hass, Malene Ringkjøbing Jensen, D.f. Hansen, Søren M. Kristensen, Jj LedAbstract:Analogous to insulin, the Relaxin-Like Factor (RLF) must undergo a structural transition to the active form prior to receptor binding. Thus, the C-terminus of the B chain of RLF folds toward the surface of the central B chain helix, causing partial obliteration of the two essential RLF receptor-binding site residues, valine B19 and tryptophan B27. Via comparison of the solution structure of a fully active C-terminally cross-linked RLF analogue with the native synthetic human RLF (hRLF), it became clear that the cross-linked analogue largely retains the essential folding of the native protein. Both proteins exist in a major and minor conformation, as revealed by multiple resonances from tryptophan B27 and adjacent residues on the B chain helix. Notably, the minor conformation is significantly more highly populated in the chemically cross-linked RLF than it is in the hRLF. In addition, compared to the unmodified molecule, subtle differences are observed within the B chain helix whereby the cross-linked derivative shows a reduced level of hydrogen bonding and significant peak broadening at the binding site residue ValB19. On the basis of these observations, we suggest that the solution structure of the native hormone represents an inactive conformer and that a dynamic equilibrium exists between the C-terminally unfolded binding conformation and the inactive conformation of the RLF.
Thomas Klonisch - One of the best experts on this subject based on the ideXlab platform.
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Molecular Human Reproduction vol.5 no.2 pp. 104–108, 1999 Expression of Relaxin-Like Factor is down-regulated in human testicular Leydig cell neoplasia
2013Co-Authors: Thomas Klonisch, Martin Bergmann, Bernd Fischer, Richard Ivell, Marga Balvers, Sabine Kliesch, Klaus StegerAbstract:4To whom correspondence should be addressed In addition to their role in steroidogenesis in the male, testicular Leydig cells constitutively express large amounts of the peptide Relaxin-Like Factor (RLF), also known as Ley-IL. The Leydig cell-derived RLF belongs to the insulin-Like superfamily, which also includes Relaxin, insulin and the insulin-Like growth Factors, and within the testis is a specific marker of Leydig cells. Little information is available either on the regulation of gene expression or on the function of this Leydig cell-derived peptide. In the present study we have investigated the expression pattern of human RLF in patients with rare Leydig cell hyperplasia and adenoma. The expression of both mRNA and protein appear to be decreased in hyperplastic Leydig cells, whereas in the Leydig cell adenomas studied, large central areas of the adenoma were devoid of RLF mRNA and protein. Only Leydig cells located at the periphery of the adenoma displayed expression of RLF, with full agreement between in-situ hybridization and immunohistochemistry. It thus appears that the expression of the RLF gene and its products are down-regulated in Leydig cell hyperplasia and adenoma, consistent with a concomitant dedifferentiation of these cells. Key words: adenoma/human testis/hyperplasia/Leydig cell/Relaxin-Like facto
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Relaxin-Like peptides in cancer.
International journal of cancer, 2003Co-Authors: Josh D. Silvertown, Alastair J. S. Summerlee, Thomas KlonischAbstract:The members of the Relaxin-Like hormone family, Relaxin and INSL3, also known as Relaxin-Like Factor (RLF) or Leydig cell-derived insulin-Like Factor (LEY-I-L), are implicated in various mechanisms associated with tumor cell growth, differentiation, invasion and neovascularization. The recent discovery of the Relaxin receptor LGR7 and the INSL3/Relaxin receptor LGR8 has provided evidence of an auto/paracrine Relaxin-Like action in tumor tissues and enables the elucidation of the cellular pathways involved in the proposed functions of Relaxin in tumor biology. Our review summarizes our current knowledge of the expression of Relaxin and INSL3 in human neoplastic tissues and discusses the etiological roles of these heterodimeric peptide hormones in cancer. Discussion of possible cellular cascades involved in actions linking Relaxin-Like peptides and neoplasia include the role of Relaxin-Like peptides in tumor cell growth and differentiation; the effect of Relaxin in stimulating the synthesis of the vasodilatory and tumor cell cytostatic and antiapoptotic molecule, nitric oxide; the potential ability of Relaxin to upregulate vascular endothelial growth Factor to promote angiogenesis and neovascularization and the concerted fine-tuned action of Relaxin on the matrix metalloproteinases on the extracellular matrix to facilitate tumor cell attachment, migration and invasion. © 2003 Wiley-Liss, Inc.
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INSL-3 is expressed in human hyperplastic and neoplastic thyrocytes.
International journal of oncology, 2003Co-Authors: Sabine Hombach-klonisch, Bernd Fischer, Cuong Hoang-vu, Astrid Kehlen, Raoul Hinze, Hans-jürgen Holzhausen, Ekkehard Weber, Henning Dralle, Thomas KlonischAbstract:The insulin-Like hormone INSL-3, also named Relaxin-Like Factor (RLF) or Leydig-derived insulin-Like peptide (LEY-IL), is expressed in various reproductive tissues and is regarded a marker of differentiation in human testicular Leydig cells. Recently, we have identified differential expression of human INSL-3 in neoplastic Leydig cells and mammary epithelial cells suggesting an involvement of INSL-3 in tumor biology. Here we have investigated the expression of INSL-3 in human thyroid carcinoma cell lines and in the human thyroid gland which has been shown to express transcripts for the G protein coupled INSL-3 receptor LGR8. When we determined the expression of INSL-3 in eight human thyroid carcinoma cell lines, a novel INSL-3 splice variant containing a 95 bp out-of-frame insertion at the beginning of exon II of the INSL-3 gene was discovered. Treatment of the human anaplastic thyroid carcinoma cell line 8505C with diethylstilbestrol (DES) caused a significant dose-dependent transcriptional down-regulation of INSL-3 and a marked up-regulation of LGR8. Employing in situ hybridization to detect INSL-3 transcripts and specific rabbit antisera against the INSL-3 proteins, both INSL-3 isoforms were detected in patients with Graves' disease (n=10), follicular carcinomas (FTC; n=12), papillary carcinomas (PTC; n=9) and undifferentiated anaplastic carcinomas (UTC; n=15). By contrast, thyrocytes of all 15 benign goiter tissues studied were devoid of both INSL-3 isoforms, mRNA and protein. Our data indicate that INSL-3 hormone is up-regulated in hyperplastic and neoplastic human thyrocytes suggesting that the INSL-3 isoforms may serve as additional markers for hyperplastic and neoplastic human thyrocytes. In the anaplastic thyroid carcinoma cell line 8505C, the regulation of both INSL-3 and LGR8 by estrogen may be the first indication of a novel hormonally responsive, auto-/paracrine INSL-3 LGR8 ligand receptor system active in human thyroid carcinoma cells.
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Cellular localization of human Relaxin-Like Factor in the cyclic endometrium and placenta
Molecular human reproduction, 2001Co-Authors: Sabine Hombach-klonisch, Bernd Fischer, Sven Seeger, G. Tscheudschilsuren, J. Buchmann, Berthold Huppertz, G Seliger, Thomas KlonischAbstract:We have studied the cellular localization of the Relaxin-Like Factor (RLF) in the histologically normal cyclic endometrium collected from days 3–26 of the menstrual cycle. RLF transcripts and protein were detected in the luminal and glandular epithelium and in stromal cells at all stages of the cyclic endometrium. Increased expression of RLF was observed in endometrial tissues in the proliferative as compared to the secretory phase, suggesting that oestrogens affect RLF gene activity in the human endometrium. The cellular localization of RLF transcripts and protein was also determined in first trimester placental tissues obtained from normal and ectopic tubal implantation sites and in third trimester placentae of normal and pre-eclamptic pregnancies. In first trimester placenta, weaker expression of RLF was observed in the syncytiotrophoblast as compared to the underlying cytotrophoblast. Extravillous trophoblast cells constitutively expressed RLF. Trophoblast cells were the main source of RLF in the human placenta and trophoblastic RLF gene activity was unaffected by either the site of implantation or the invasive properties of the cytotrophoblast as demonstrated by samples from patients with tubal implantation and pre-eclampsia respectively. Decidual cells weakly expressed RLF. The presence of unprocessed and cleaved immunoreactive RLF in term placenta was determined by Western analysis. The above results suggest a functional role for both RLF isoforms within normal placental tissue.
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Molecular Remodeling of Members of the Relaxin Family During Primate Evolution
Molecular biology and evolution, 2001Co-Authors: Thomas Klonisch, Bernd Fischer, Frank Tetens, Christine Froehlich, Sabine Hombach-klonischAbstract:The members of the Relaxin family include the two hormones Relaxin and the structurally closely related Relaxin-Like Factor (RLF). Relaxin displays high sequence variability within and between taxonomic groups among land animals. Widely regarded as a hormone of the female reproductive tract, Relaxin is expressed in the ovary and at the feto-maternal interface [1]. Known as a marker of human postpubertal testicular Leydig cells in various species [2–4], RLF is essential for the development of the Gubernaculum testis. Male RLF -/- mice are infertile due to impaired testicular descent resulting in cryptorchidism [5, 6]. Strepsirrhini, which includes the Afro-Asian loris and the Malagasy lemurs, are assumed to have diverged from other primates about 65 Million years ago (Myr) and have developed independently for over 60 Myr [7]. To study the dynamics in the molecular remodelling of both members of the Relaxin family during primate evolution, we have cloned the cDNA sequences of the preproRelaxins and RLF in the African lorisiform Galago crassicaudatus (Gcr) and of preproRelaxin in the Malagasy lemur Varecia variegata (Vva) which is phylogenetically regarded plesiomorphic to all Malagasy lemurs [8].
Sabine Hombach-klonisch - One of the best experts on this subject based on the ideXlab platform.
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Canine Relaxin-Like Factor: Unique Molecular Structure and Differential Expression Within Reproductive Tissues of the Dog
2016Co-Authors: Sabine Hombach-klonischAbstract:Employing postpubertal testicular tissue, we determined the cDNA coding sequence of a truncated canine Relaxin-Like Factor (RLF) consisting of a signal peptide of 28 amino acids (aa), a B-domain of 23 aa, a truncated C-domain of 34 aa, and an A domain of 26 aa, respectively. Within the B-domain of canine RLF, the putative Relaxin receptor binding motif contained a sin-gle substitution with the C-terminal arginine replaced by a ser-ine residue, and the putative RLF receptor binding motif was truncated. Leydig cells specifically expressed RLF in the normal postpubertal and cryptochid testis as well as in testicular Leydig cell adenoma. The epididymis was an additional source of RLF in the dog. In the female reproductive tract, expression of im-munoreactive RLF and Relaxin were compared. Within the ovary, RLF, but not Relaxin, was detected in follicular theca interna an
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INSL-3 is expressed in human hyperplastic and neoplastic thyrocytes.
International journal of oncology, 2003Co-Authors: Sabine Hombach-klonisch, Bernd Fischer, Cuong Hoang-vu, Astrid Kehlen, Raoul Hinze, Hans-jürgen Holzhausen, Ekkehard Weber, Henning Dralle, Thomas KlonischAbstract:The insulin-Like hormone INSL-3, also named Relaxin-Like Factor (RLF) or Leydig-derived insulin-Like peptide (LEY-IL), is expressed in various reproductive tissues and is regarded a marker of differentiation in human testicular Leydig cells. Recently, we have identified differential expression of human INSL-3 in neoplastic Leydig cells and mammary epithelial cells suggesting an involvement of INSL-3 in tumor biology. Here we have investigated the expression of INSL-3 in human thyroid carcinoma cell lines and in the human thyroid gland which has been shown to express transcripts for the G protein coupled INSL-3 receptor LGR8. When we determined the expression of INSL-3 in eight human thyroid carcinoma cell lines, a novel INSL-3 splice variant containing a 95 bp out-of-frame insertion at the beginning of exon II of the INSL-3 gene was discovered. Treatment of the human anaplastic thyroid carcinoma cell line 8505C with diethylstilbestrol (DES) caused a significant dose-dependent transcriptional down-regulation of INSL-3 and a marked up-regulation of LGR8. Employing in situ hybridization to detect INSL-3 transcripts and specific rabbit antisera against the INSL-3 proteins, both INSL-3 isoforms were detected in patients with Graves' disease (n=10), follicular carcinomas (FTC; n=12), papillary carcinomas (PTC; n=9) and undifferentiated anaplastic carcinomas (UTC; n=15). By contrast, thyrocytes of all 15 benign goiter tissues studied were devoid of both INSL-3 isoforms, mRNA and protein. Our data indicate that INSL-3 hormone is up-regulated in hyperplastic and neoplastic human thyrocytes suggesting that the INSL-3 isoforms may serve as additional markers for hyperplastic and neoplastic human thyrocytes. In the anaplastic thyroid carcinoma cell line 8505C, the regulation of both INSL-3 and LGR8 by estrogen may be the first indication of a novel hormonally responsive, auto-/paracrine INSL-3 LGR8 ligand receptor system active in human thyroid carcinoma cells.
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Cellular localization of human Relaxin-Like Factor in the cyclic endometrium and placenta
Molecular human reproduction, 2001Co-Authors: Sabine Hombach-klonisch, Bernd Fischer, Sven Seeger, G. Tscheudschilsuren, J. Buchmann, Berthold Huppertz, G Seliger, Thomas KlonischAbstract:We have studied the cellular localization of the Relaxin-Like Factor (RLF) in the histologically normal cyclic endometrium collected from days 3–26 of the menstrual cycle. RLF transcripts and protein were detected in the luminal and glandular epithelium and in stromal cells at all stages of the cyclic endometrium. Increased expression of RLF was observed in endometrial tissues in the proliferative as compared to the secretory phase, suggesting that oestrogens affect RLF gene activity in the human endometrium. The cellular localization of RLF transcripts and protein was also determined in first trimester placental tissues obtained from normal and ectopic tubal implantation sites and in third trimester placentae of normal and pre-eclamptic pregnancies. In first trimester placenta, weaker expression of RLF was observed in the syncytiotrophoblast as compared to the underlying cytotrophoblast. Extravillous trophoblast cells constitutively expressed RLF. Trophoblast cells were the main source of RLF in the human placenta and trophoblastic RLF gene activity was unaffected by either the site of implantation or the invasive properties of the cytotrophoblast as demonstrated by samples from patients with tubal implantation and pre-eclampsia respectively. Decidual cells weakly expressed RLF. The presence of unprocessed and cleaved immunoreactive RLF in term placenta was determined by Western analysis. The above results suggest a functional role for both RLF isoforms within normal placental tissue.
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Molecular Remodeling of Members of the Relaxin Family During Primate Evolution
Molecular biology and evolution, 2001Co-Authors: Thomas Klonisch, Bernd Fischer, Frank Tetens, Christine Froehlich, Sabine Hombach-klonischAbstract:The members of the Relaxin family include the two hormones Relaxin and the structurally closely related Relaxin-Like Factor (RLF). Relaxin displays high sequence variability within and between taxonomic groups among land animals. Widely regarded as a hormone of the female reproductive tract, Relaxin is expressed in the ovary and at the feto-maternal interface [1]. Known as a marker of human postpubertal testicular Leydig cells in various species [2–4], RLF is essential for the development of the Gubernaculum testis. Male RLF -/- mice are infertile due to impaired testicular descent resulting in cryptorchidism [5, 6]. Strepsirrhini, which includes the Afro-Asian loris and the Malagasy lemurs, are assumed to have diverged from other primates about 65 Million years ago (Myr) and have developed independently for over 60 Myr [7]. To study the dynamics in the molecular remodelling of both members of the Relaxin family during primate evolution, we have cloned the cDNA sequences of the preproRelaxins and RLF in the African lorisiform Galago crassicaudatus (Gcr) and of preproRelaxin in the Malagasy lemur Varecia variegata (Vva) which is phylogenetically regarded plesiomorphic to all Malagasy lemurs [8].
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Canine Relaxin-Like Factor: Unique Molecular Structure and Differential Expression Within Reproductive Tissues of the Dog
Biology of reproduction, 2001Co-Authors: Thomas Klonisch, Martin Bergmann, Bernd Fischer, Klaus Steger, Johannes Kauffold, Rudolf Leiser, Sabine Hombach-klonischAbstract:Employing postpubertal testicular tissue, we determined the cDNA coding sequence of a truncated canine Relaxin-Like Factor (RLF) consisting of a signal peptide of 28 amino acids (aa), a B-domain of 23 aa, a truncated C-domain of 34 aa, and an A domain of 26 aa, respectively. Within the B-domain of canine RLF, the putative Relaxin receptor binding motif contained a single substitution with the C-terminal arginine replaced by a serine residue, and the putative RLF receptor binding motif was truncated. Leydig cells specifically expressed RLF in the normal postpubertal and cryptochid testis as well as in testicular Leydig cell adenoma. The epididymis was an additional source of RLF in the dog. In the female reproductive tract, expression of immunoreactive RLF and Relaxin were compared. Within the ovary, RLF, but not Relaxin, was detected in follicular theca interna and granulosa cells and the corpus luteum. In the nonpregnant uterus, luminal and glandular epithelium coexpressed RLF and Relaxin. Uteroplacental tissue at early stages of gestation revealed RLF expression in the proliferative fetal villous cytotrophoblast and in maternal uterine cells. In the mature canine placenta, the trophoblast surrounding the maternal blood vessels and the hemophagous cytotrophoblast of the paraplacental zone expressed RLF. Canine Relaxin was absent in the paraplacental areas. Western analysis of placental tissue extracts revealed the presence of specific immunoreactive bands Likely resembling unprocessed and enzymatically cleaved RLF. Differential expression of RLF and Relaxin appears to reflect distinct autocrine and paracrine functions of RLF in canine reproductive tissues.