273 results on '"Peter Herrlich"'
Search Results
2. The LIM domain protein nTRIP6 modulates the dynamics of myogenic differentiation
- Author
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Tannaz Norizadeh Abbariki, Zita Gonda, Denise Kemler, Pavel Urbanek, Tabea Wagner, Margarethe Litfin, Zhao-Qi Wang, Peter Herrlich, and Olivier Kassel
- Subjects
Medicine ,Science - Abstract
Abstract The process of myogenesis which operates during skeletal muscle regeneration involves the activation of muscle stem cells, the so-called satellite cells. These then give rise to proliferating progenitors, the myoblasts which subsequently exit the cell cycle and differentiate into committed precursors, the myocytes. Ultimately, the fusion of myocytes leads to myofiber formation. Here we reveal a role for the transcriptional co-regulator nTRIP6, the nuclear isoform of the LIM-domain protein TRIP6, in the temporal control of myogenesis. In an in vitro model of myogenesis, the expression of nTRIP6 is transiently up-regulated at the transition between proliferation and differentiation, whereas that of the cytosolic isoform TRIP6 is not altered. Selectively blocking nTRIP6 function results in accelerated early differentiation followed by deregulated late differentiation and fusion. Thus, the transient increase in nTRIP6 expression appears to prevent premature differentiation. Accordingly, knocking out the Trip6 gene in satellite cells leads to deregulated skeletal muscle regeneration dynamics in the mouse. Thus, dynamic changes in nTRIP6 expression contributes to the temporal control of myogenesis.
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- 2021
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3. Deletion of Cd44 Inhibits Metastasis Formation of Liver Cancer in Nf2-Mutant Mice
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Monserrat Gerardo-Ramírez, Vanessa Giam, Diana Becker, Marco Groth, Nils Hartmann, Helen Morrison, Helen L. May-Simera, Markus P. Radsak, Jens U. Marquardt, Peter R. Galle, Peter Herrlich, Beate K. Straub, and Monika Hartmann
- Subjects
CD44 ,Merlin ,NF2 ,liver cancer ,HCC ,ICAM-1 ,Cytology ,QH573-671 - Abstract
Primary liver cancer is the third leading cause of cancer-related death worldwide. An increasing body of evidence suggests that the Hippo tumor suppressor pathway plays a critical role in restricting cell proliferation and determining cell fate during physiological and pathological processes in the liver. Merlin (Moesin-Ezrin-Radixin-like protein) encoded by the NF2 (neurofibromatosis type 2) gene is an upstream regulator of the Hippo signaling pathway. Targeting of Merlin to the plasma membrane seems to be crucial for its major tumor-suppressive functions; this is facilitated by interactions with membrane-associated proteins, including CD44 (cluster of differentiation 44). Mutations within the CD44-binding domain of Merlin have been reported in many human cancers. This study evaluated the relative contribution of CD44- and Merlin-dependent processes to the development and progression of liver tumors. To this end, mice with a liver-specific deletion of the Nf2 gene were crossed with Cd44-knockout mice and subjected to extensive histological, biochemical and molecular analyses. In addition, cells were isolated from mutant livers and analyzed by in vitro assays. Deletion of Nf2 in the liver led to substantial liver enlargement and generation of hepatocellular carcinomas (HCCs), intrahepatic cholangiocarcinomas (iCCAs), as well as mixed hepatocellular cholangiocarcinomas. Whilst deletion of Cd44 had no influence on liver size or primary liver tumor development, it significantly inhibited metastasis formation in Nf2-mutant mice. CD44 upregulates expression of integrin β2 and promotes transendothelial migration of liver cancer cells, which may facilitate metastatic spreading. Overall, our results suggest that CD44 may be a promising target for intervening with metastatic spreading of liver cancer.
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- 2023
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4. Spindle Misorientation of Cerebral and Cerebellar Progenitors Is a Mechanistic Cause of Megalencephaly
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Huaibiao Li, Torsten Kroll, Jürgen Moll, Lucien Frappart, Peter Herrlich, Heike Heuer, and Aspasia Ploubidou
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oriented division ,cerebral neuroprogenitor ,cerebral cortex ,cerebellar granule cell precursor ,cerebellum differentiation ,neurogenesis ,brain development ,RHAMM ,neuronal progenitor ,Medicine (General) ,R5-920 ,Biology (General) ,QH301-705.5 - Abstract
Misoriented division of neuroprogenitors, by loss-of-function studies of centrosome or spindle components, has been linked to the developmental brain defects microcephaly and lissencephaly. As these approaches also affect centrosome biogenesis, spindle assembly, or cell-cycle progression, the resulting pathologies cannot be attributed solely to spindle misorientation. To address this issue, we employed a truncation of the spindle-orienting protein RHAMM. This truncation of the RHAMM centrosome-targeting domain does not have an impact on centrosome biogenesis or on spindle assembly in vivo. The RHAMM mutants exhibit misorientation of the division plane of neuroprogenitors, without affecting the division rate of these cells, resulting against expectation in megalencephaly associated with cerebral cortex thickening, cerebellum enlargement, and premature cerebellum differentiation. We conclude that RHAMM associates with the spindle of neuroprogenitor cells via its centrosome-targeting domain, where it regulates differentiation in the developing brain by orienting the spindle.
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- 2017
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5. Gamma secretase dependent release of the CD44 cytoplasmic tail upregulates IFI16 in cd44-/- tumor cells, MEFs and macrophages.
- Author
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Kristin Schultz, Christina Grieger Lindner, Yong Li, Pavel Urbánek, Anne Ruschel, Kerstin Minnich, Dunja Bruder, Marcus Gereke, Antonio Sechi, and Peter Herrlich
- Subjects
Medicine ,Science - Abstract
The adhesion molecule and co-receptor of receptor tyrosine kinases, CD44, is expressed in all cells of the immune system, but also in numerous non-immune cells. CD44 plays roles in the cellular response to different pathogens. The molecular actions of CD44 during these processes are by and large still unknown. The CD44 molecule undergoes a sequential proteolytic cleavage which leads to the release of a soluble intracellular domain (CD44-ICD). Previous reports had shown that the CD44-ICD is taken up into the nucleus where it enhances transcription of specific target genes. By RNA profiling we identified a CD44-dependent transcriptional increase of interferon-responsive genes, among them IFI16. IFI16 is important in the innate immune response. It senses and binds pathogenic DNA and, together with cGAS, activates the cGAS-cGAMP-STING pathway and induces the expression of genes relevant for the response, e.g. IFN-β. Our results show that the enhancement of IFI16 expression depended on CD44 cleavage. A CD44-negative tumor cell line, embryonic fibroblasts and bone marrow-derived macrophages from cd44-/- mice were reduced in their response to IFN-γ, to viral DNA fragments and to Listeria monocytogenes infection. We could rescue the deficiency of CD44 negative RPM-MC cells and cd44-/- MEFs by expressing only the soluble CD44-ICD in the absence of any other CD44 domain. Expression of the CD44-ICD carrying a mutation that prevented the uptake into the nucleus, could not rescue the absence of CD44. This molecular aspect of regulation by CD44 may explain part of the immune phenotypes of mice with cd44 gene disruption.
- Published
- 2018
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6. RHAMM deficiency disrupts folliculogenesis resulting in female hypofertility
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Huaibiao Li, Jürgen Moll, Anne Winkler, Lucien Frappart, Stéphane Brunet, Jana Hamann, Torsten Kroll, Marie-Hélène Verlhac, Heike Heuer, Peter Herrlich, and Aspasia Ploubidou
- Subjects
Gametogenesis ,Folliculogenesis ,Hypofertility ,Spindle ,RHAMM ,Oriented mitosis ,Centrosome ,Science ,Biology (General) ,QH301-705.5 - Abstract
The postnatal mammalian ovary contains the primary follicles, each comprising an immature oocyte surrounded by a layer of somatic granulosa cells. Oocytes reach meiotic and developmental competence via folliculogenesis. During this process, the granulosa cells proliferate massively around the oocyte, form an extensive extracellular matrix (ECM) and differentiate into cumulus cells. As the ECM component hyaluronic acid (HA) is thought to form the backbone of the oocyte-granulosa cell complex, we deleted the relevant domain of the Receptor for HA Mediated Motility (RHAMM) gene in the mouse. This resulted in folliculogenesis defects and female hypofertility, although HA-induced signalling was not affected. We report that wild-type RHAMM localises at the mitotic spindle of granulosa cells, surrounding the oocyte. Deletion of the RHAMM C-terminus in vivo abolishes its spindle association, resulting in impaired spindle orientation in the dividing granulosa cells, folliculogenesis defects and subsequent female hypofertility. These data reveal the first identified physiological function for RHAMM, during oogenesis, and the importance of this spindle-associated function for female fertility.
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- 2015
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7. The LIM domain protein nTRIP6 recruits the mediator complex to AP-1-regulated promoters.
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Markus E Diefenbacher, Daniela Reich, Oliver Dahley, Denise Kemler, Margarethe Litfin, Peter Herrlich, and Olivier Kassel
- Subjects
Medicine ,Science - Abstract
Several LIM domain proteins regulate transcription. They are thought to act through their LIM protein-protein interaction domains as adaptors for the recruitment of transcriptional co-regulators. An intriguing example is nTRIP6, the nuclear isoform of the focal adhesion protein TRIP6. nTRIP6 interacts with AP-1 and enhances its transcriptional activity. nTRIP6 is also essential for the transrepression of AP-1 by the glucocorticoid receptor (GR), by mediating GR tethering to promoter-bound AP-1. Here we report on the molecular mechanism by which nTRIP6 exerts these effects. Both the LIM domains and the pre-LIM region of nTRIP6 are necessary for its co-activator function for AP-1. Discrete domains within the pre-LIM region mediate the dimerization of nTRIP6 at the promoter, which enables the recruitment of the Mediator complex subunits THRAP3 and Med1. This recruitment is blocked by GR, through a competition between GR and THRAP3 for the interaction with the LIM domains of nTRIP6. Thus, nTRIP6 both positively and negatively regulates transcription by orchestrating the recruitment of the Mediator complex to AP-1-regulated promoters.
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- 2014
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8. CD44 Promotes intoxication by the clostridial iota-family toxins.
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Darran J Wigelsworth, Gordon Ruthel, Leonie Schnell, Peter Herrlich, Josip Blonder, Timothy D Veenstra, Robert J Carman, Tracy D Wilkins, Guy Tran Van Nhieu, Serge Pauillac, Maryse Gibert, Nathalie Sauvonnet, Bradley G Stiles, Michel R Popoff, and Holger Barth
- Subjects
Medicine ,Science - Abstract
Various pathogenic clostridia produce binary protein toxins associated with enteric diseases of humans and animals. Separate binding/translocation (B) components bind to a protein receptor on the cell surface, assemble with enzymatic (A) component(s), and mediate endocytosis of the toxin complex. Ultimately there is translocation of A component(s) from acidified endosomes into the cytosol, leading to destruction of the actin cytoskeleton. Our results revealed that CD44, a multifunctional surface protein of mammalian cells, facilitates intoxication by the iota family of clostridial binary toxins. Specific antibody against CD44 inhibited cytotoxicity of the prototypical Clostridium perfringens iota toxin. Versus CD44(+) melanoma cells, those lacking CD44 bound less toxin and were dose-dependently resistant to C. perfringens iota, as well as Clostridium difficile and Clostridium spiroforme iota-like, toxins. Purified CD44 specifically interacted in vitro with iota and iota-like, but not related Clostridium botulinum C2, toxins. Furthermore, CD44 knockout mice were resistant to iota toxin lethality. Collective data reveal an important role for CD44 during intoxication by a family of clostridial binary toxins.
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- 2012
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9. Activation of Ras requires the ERM-dependent link of actin to the plasma membrane.
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Tobias Sperka, Katja J Geissler, Ulrike Merkel, Ingmar Scholl, Ignacio Rubio, Peter Herrlich, and Helen L Morrison
- Subjects
Medicine ,Science - Abstract
Receptor tyrosine kinases (RTKs) participate in a multitude of signaling pathways, some of them via the small G-protein Ras. An important component in the activation of Ras is Son of sevenless (SOS), which catalyzes the nucleotide exchange on Ras.We can now demonstrate that the activation of Ras requires, in addition, the essential participation of ezrin, radixin and/or moesin (ERM), a family of actin-binding proteins, and of actin. Disrupting either the interaction of the ERM proteins with co-receptors, down-regulation of ERM proteins by siRNA, expression of dominant-negative mutants of the ERM proteins or disruption of F-actin, abolishes growth factor-induced Ras activation. Ezrin/actin catalyzes the formation of a multiprotein complex consisting of RTK, co-receptor, Grb2, SOS and Ras. We also identify binding sites for both Ras and SOS on ezrin; mutations of these binding sites destroy the interactions and inhibit Ras activation. Finally, we show that the formation of the ezrin-dependent complex is necessary to enhance the catalytic activity of SOS and thereby Ras activation.Taking these findings together, we propose that the ERM proteins are novel scaffolds at the level of SOS activity control, which is relevant for both normal Ras function and dysfunction known to occur in several human cancers.
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- 2011
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10. Supplemental Material and Methods from Tumor Suppressor NF2 Blocks Cellular Migration by Inhibiting Ectodomain Cleavage of CD44
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Peter Herrlich, Andreas Herrlich, Helen Morrison, Yong Li, Sandra Böhme, Anne Ruschel, Liseth M. Parra, and Monika Hartmann
- Abstract
Supplemental Material and Methods. Cell lines, Transfections, Precipitation of Proteins by TCA-DOC , Co-immunoprecipitation (Co-IP) from Cell Lysates, Preparation of Cell Lysates
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- 2023
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11. Supplemental Figure Legends from Tumor Suppressor NF2 Blocks Cellular Migration by Inhibiting Ectodomain Cleavage of CD44
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Peter Herrlich, Andreas Herrlich, Helen Morrison, Yong Li, Sandra Böhme, Anne Ruschel, Liseth M. Parra, and Monika Hartmann
- Abstract
Supplemental Figure Legends S1-S7. Supplemental Figure Legends
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- 2023
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12. Supplemental Figures S1-S7 from Tumor Suppressor NF2 Blocks Cellular Migration by Inhibiting Ectodomain Cleavage of CD44
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Peter Herrlich, Andreas Herrlich, Helen Morrison, Yong Li, Sandra Böhme, Anne Ruschel, Liseth M. Parra, and Monika Hartmann
- Abstract
Supplemental Figures S1-S7: Supplemental Figure S1: The effect of γ-secretase inhibition on ectodomain cleavage Supplemental Figure S2. Regulated cleavage targets substrates after surface expression Supplemental Figure S3: Interaction between CD44 and Merlin. Supplemental Figure S4: The tumor suppressor merlin (Nf2) inhibits CD44 cleavage. Supplemental Figure S5. Exemplified analysis of the constructs used in the migration assay of Figure 7A and Supplemental Figure 6 Supplemental Figure S6: Examplified photographs of one of the scratch assays with MEFs as shown in Figure 7A. Supplemental Figure S7: Loading diagrams of Figures 3B and 4C
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- 2023
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13. Supplemental Materials & Methods from Impaired Planar Germ Cell Division in the Testis, Caused by Dissociation of RHAMM from the Spindle, Results in Hypofertility and Seminoma
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Aspasia Ploubidou, Peter Herrlich, Kurt Zatloukal, Matthias Platzer, Bodo M.H. Lange, Heike Heuer, Marie-Laure Yaspo, Moritz Schütte, Stefan Taudien, Marco Groth, Iris Kufferath, Jana Hamann, Torsten Kroll, Anne Winkler, Jürgen Moll, Lucien Frappart, and Huaibiao Li
- Abstract
Supplemental Materials & Methods and the references cited within.
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- 2023
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14. Supplemental Figure Legends from Impaired Planar Germ Cell Division in the Testis, Caused by Dissociation of RHAMM from the Spindle, Results in Hypofertility and Seminoma
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Aspasia Ploubidou, Peter Herrlich, Kurt Zatloukal, Matthias Platzer, Bodo M.H. Lange, Heike Heuer, Marie-Laure Yaspo, Moritz Schütte, Stefan Taudien, Marco Groth, Iris Kufferath, Jana Hamann, Torsten Kroll, Anne Winkler, Jürgen Moll, Lucien Frappart, and Huaibiao Li
- Abstract
Legends of supplemental figures S1-S5
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- 2023
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15. Supplemental Table S1 from Impaired Planar Germ Cell Division in the Testis, Caused by Dissociation of RHAMM from the Spindle, Results in Hypofertility and Seminoma
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Aspasia Ploubidou, Peter Herrlich, Kurt Zatloukal, Matthias Platzer, Bodo M.H. Lange, Heike Heuer, Marie-Laure Yaspo, Moritz Schütte, Stefan Taudien, Marco Groth, Iris Kufferath, Jana Hamann, Torsten Kroll, Anne Winkler, Jürgen Moll, Lucien Frappart, and Huaibiao Li
- Abstract
Overview of human testis biopsy samples, which were analyzed for RHAMM parameters (mRNA expression, protein localization, locus variants, allele frequencies) as well as for expression of CFIm25 and of 12 TGCT susceptibility genes.
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- 2023
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16. Supplemental Figure S1 from Impaired Planar Germ Cell Division in the Testis, Caused by Dissociation of RHAMM from the Spindle, Results in Hypofertility and Seminoma
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Aspasia Ploubidou, Peter Herrlich, Kurt Zatloukal, Matthias Platzer, Bodo M.H. Lange, Heike Heuer, Marie-Laure Yaspo, Moritz Schütte, Stefan Taudien, Marco Groth, Iris Kufferath, Jana Hamann, Torsten Kroll, Anne Winkler, Jürgen Moll, Lucien Frappart, and Huaibiao Li
- Abstract
Its centrosome-targeting domain is indispensable for RHAMM spindle localization and it contributes to maintenance of spindle integrity in vitro.
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- 2023
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17. Data from Impaired Planar Germ Cell Division in the Testis, Caused by Dissociation of RHAMM from the Spindle, Results in Hypofertility and Seminoma
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Aspasia Ploubidou, Peter Herrlich, Kurt Zatloukal, Matthias Platzer, Bodo M.H. Lange, Heike Heuer, Marie-Laure Yaspo, Moritz Schütte, Stefan Taudien, Marco Groth, Iris Kufferath, Jana Hamann, Torsten Kroll, Anne Winkler, Jürgen Moll, Lucien Frappart, and Huaibiao Li
- Abstract
Hypofertility is a risk factor for the development of testicular germ cell tumors (TGCT), but the initiating event linking these pathologies is unknown. We hypothesized that excessive planar division of undifferentiated germ cells promotes their self-renewal and TGCT development. However, our results obtained from mouse models and seminoma patients demonstrated the opposite. Defective planar divisions of undifferentiated germ cells caused their premature exit from the seminiferous tubule niche, resulting in germ cell depletion, hypofertility, intratubular germ cell neoplasias, and seminoma development. Oriented divisions of germ cells, which determine their fate, were regulated by spindle-associated RHAMM—a function we found to be abolished in 96% of human seminomas. Mechanistically, RHAMM expression is regulated by the testis-specific polyadenylation protein CFIm25, which is downregulated in the human seminomas. These results suggested that spindle misorientation is oncogenic, not by promoting self‐renewing germ cell divisions within the niche, but by prematurely displacing proliferating cells from their normal epithelial milieu. Furthermore, they suggested RHAMM loss-of-function and spindle misorientation as an initiating event underlying both hypofertility and TGCT initiation. These findings identify spindle-associated RHAMM as an intrinsic regulator of male germ cell fate and as a gatekeeper preventing initiation of TGCTs. Cancer Res; 76(21); 6382–95. ©2016 AACR.
- Published
- 2023
- Full Text
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18. Data from Merlin/Neurofibromatosis Type 2 Suppresses Growth by Inhibiting the Activation of Ras and Rac
- Author
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Peter Herrlich, Helmut Ponta, Marco Giovannini, Jan Manent, Tobias Sperka, and Helen Morrison
- Abstract
The small G-protein Ras is a tightly controlled regulator of cell fate. Prolonged or persistent arrest in the activated GTP-loaded state by mutation of Ras as in lung cancer or in a Ras–GTPase-activating protein as in neurofibromatosis type 1 promotes tumorigenesis. We now show that the tumor-suppressor protein merlin (mutated in neurofibromatosis type 2) also controls Ras activity. Systematic analysis of growth factor signaling located the step of merlin interference to the activation of Ras and Rac. Merlin independently uncouples both Ras and Rac from growth factor signals. In the case of Ras, merlin acts downstream of the receptor tyrosine kinase-growth factor receptor binding protein 2 (Grb2)-SOS complex. However, merlin does not bind either SOS or Ras, but it counteracts the ERM (ezrin, radixin, moesin)–dependent activation of Ras, which correlates with the formation of a complex comprising ERM proteins, Grb2, SOS, Ras, and filamentous actin. Because efficient signaling from Ras requires Rac-p21-activated kinase–dependent phosphorylations of Raf and mitogen-activated protein/extracellular signal-regulated kinase kinase, merlin can also inhibit signal transfer from dominantly active Ras mutants. We propose that the interference of merlin with Ras- and Rac-dependent signal transfer represents part of the tumor-suppressive action of merlin. [Cancer Res 2007;67(2):520–7]
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- 2023
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19. Supplementary Figure 3 from Merlin/Neurofibromatosis Type 2 Suppresses Growth by Inhibiting the Activation of Ras and Rac
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Peter Herrlich, Helmut Ponta, Marco Giovannini, Jan Manent, Tobias Sperka, and Helen Morrison
- Abstract
Supplementary Figure 3 from Merlin/Neurofibromatosis Type 2 Suppresses Growth by Inhibiting the Activation of Ras and Rac
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- 2023
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20. Supplementary Figure 1 from Merlin/Neurofibromatosis Type 2 Suppresses Growth by Inhibiting the Activation of Ras and Rac
- Author
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Peter Herrlich, Helmut Ponta, Marco Giovannini, Jan Manent, Tobias Sperka, and Helen Morrison
- Abstract
Supplementary Figure 1 from Merlin/Neurofibromatosis Type 2 Suppresses Growth by Inhibiting the Activation of Ras and Rac
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- 2023
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21. Supplementary Figure 2 from Merlin/Neurofibromatosis Type 2 Suppresses Growth by Inhibiting the Activation of Ras and Rac
- Author
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Peter Herrlich, Helmut Ponta, Marco Giovannini, Jan Manent, Tobias Sperka, and Helen Morrison
- Abstract
Supplementary Figure 2 from Merlin/Neurofibromatosis Type 2 Suppresses Growth by Inhibiting the Activation of Ras and Rac
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- 2023
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22. Supplementary Figure 1 Legend from Merlin/Neurofibromatosis Type 2 Suppresses Growth by Inhibiting the Activation of Ras and Rac
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Peter Herrlich, Helmut Ponta, Marco Giovannini, Jan Manent, Tobias Sperka, and Helen Morrison
- Abstract
Supplementary Figure 1 Legend from Merlin/Neurofibromatosis Type 2 Suppresses Growth by Inhibiting the Activation of Ras and Rac
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- 2023
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23. CD44 Contributes to the Regulation of MDR1 Protein and Doxorubicin Chemoresistance in Osteosarcoma
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Monserrat Gerardo-Ramírez, Friederike L. Keggenhoff, Vanessa Giam, Diana Becker, Marco Groth, Nils Hartmann, Beate K. Straub, Helen Morrison, Peter R. Galle, Jens U. Marquardt, Peter Herrlich, and Monika Hartmann
- Subjects
Osteosarcoma ,Organic Chemistry ,Bone Neoplasms ,General Medicine ,Catalysis ,Computer Science Applications ,Gene Expression Regulation, Neoplastic ,Inorganic Chemistry ,Mice ,Hyaluronan Receptors ,Doxorubicin ,Drug Resistance, Neoplasm ,Cell Line, Tumor ,Animals ,Humans ,CD44 ,MDR1 ,bone tumors ,osteosarcoma ,hyaluronic acid ,proteolytic cleavage ,ATP Binding Cassette Transporter, Subfamily B, Member 1 ,Tumor Suppressor Protein p53 ,Physical and Theoretical Chemistry ,Molecular Biology ,Spectroscopy - Abstract
Osteosarcoma is the most common type of pediatric bone tumor. Despite great advances in chemotherapy during the past decades, the survival rates of osteosarcoma patients remain unsatisfactory. Drug resistance is one of the main reasons, leading to treatment failure and poor prognosis. Previous reports correlated expression of cluster of differentiation 44 (CD44) with drug resistance and poor survival of osteosarcoma patients, however the underlying mechanisms are poorly defined. Here, we investigated the role of CD44 in the regulation of drug chemoresistance, using osteosarcoma cells isolated from mice carrying a mutation of the tumor suppressor neurofibromatosis type 2 (Nf2) gene. CD44 expression was knocked-down in the cells using CRISPR/Cas9 approach. Subsequently, CD44 isoforms and mutants were re-introduced to investigate CD44-dependent processes. Sensitivity to doxorubicin was analyzed in the osteosarcoma cells with modified CD44 expression by immunoblot, colony formation- and WST-1 assay. To dissect the molecular alterations induced by deletion of Cd44, RNA sequencing was performed on Cd44-positive and Cd44-negative primary osteosarcoma tissues isolated from Nf2-mutant mice. Subsequently, expression of candidate genes was evaluated by quantitative reverse transcription PCR (qRT-PCR). Our results indicate that CD44 increases the resistance of osteosarcoma cells to doxorubicin by up-regulating the levels of multidrug resistance (MDR) 1 protein expression, and suggest the role of proteolytically released CD44 intracellular domain, and hyaluronan interactions in this process. Moreover, high throughput sequencing analysis identified differential regulation of several apoptosis-related genes in Cd44-positive and -negative primary osteosarcomas, including p53 apoptosis effector related to PMP-22 (Perp). Deletion of Cd44 in osteosarcoma cells led to doxorubicin-dependent p53 activation and a profound increase in Perp mRNA expression. Overall, our results suggest that CD44 might be an important regulator of drug resistance and suggest that targeting CD44 can sensitize osteosarcoma to standard chemotherapy.
- Published
- 2022
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24. Transcriptional Regulation
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Jan Tuckermann, Peter Herrlich, and Giorgio Caratti
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- 2021
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25. cis- and trans-Acting Genetic Elements Responsible for Induction of Specific Genes by Tumor Promoters, Serum Factors, and Stress
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Michael Karin and Peter Herrlich
- Subjects
Chemistry ,Tumor Promoters ,Gene ,Cis–trans isomerism ,Cell biology - Published
- 2020
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26. Ultraviolet Irradiation and Phorbol Esters Induce Gene Transcription by Different Mechanisms
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Adriana Radler-Pohl, Christoph Sachsenmaier, Bernd Stein, Mirko Vanetti, Peter Herrlich, Christine Lücke-Huhle, Marcus Krämer, Harald König, Hans-Peter Auer, Hans J. Rahmsdorf, and Stephan Gebel
- Subjects
chemistry.chemical_compound ,Chemistry ,Ultraviolet irradiation ,Phorbol esters ,Molecular biology - Published
- 2020
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27. Impaired Planar Germ Cell Division in the Testis, Caused by Dissociation of RHAMM from the Spindle, Results in Hypofertility and Seminoma
- Author
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Anne Winkler, Marco Groth, Moritz Schütte, Stefan Taudien, Aspasia Ploubidou, Jürgen Moll, Iris Kufferath, Kurt Zatloukal, Peter Herrlich, Huaibiao Li, Heike Heuer, Lucien Frappart, Torsten Kroll, Marie-Laure Yaspo, Matthias Platzer, Bodo Lange, and Jana Hamann
- Subjects
Male ,0301 basic medicine ,endocrine system ,Cancer Research ,Cell division ,Polyadenylation ,Apoptosis ,Spindle Apparatus ,Biology ,Extracellular matrix ,Mice ,03 medical and health sciences ,Testicular Neoplasms ,Testis ,medicine ,Animals ,Humans ,Extracellular Matrix Proteins ,Seminoma ,Neoplasms, Germ Cell and Embryonal ,medicine.disease ,Cell biology ,Spindle apparatus ,Fertility ,Hyaluronan Receptors ,030104 developmental biology ,Seminiferous tubule ,medicine.anatomical_structure ,Oncology ,Immunology ,Tumor Suppressor Protein p53 ,Cell Division ,Germ cell ,HeLa Cells - Abstract
Hypofertility is a risk factor for the development of testicular germ cell tumors (TGCT), but the initiating event linking these pathologies is unknown. We hypothesized that excessive planar division of undifferentiated germ cells promotes their self-renewal and TGCT development. However, our results obtained from mouse models and seminoma patients demonstrated the opposite. Defective planar divisions of undifferentiated germ cells caused their premature exit from the seminiferous tubule niche, resulting in germ cell depletion, hypofertility, intratubular germ cell neoplasias, and seminoma development. Oriented divisions of germ cells, which determine their fate, were regulated by spindle-associated RHAMM—a function we found to be abolished in 96% of human seminomas. Mechanistically, RHAMM expression is regulated by the testis-specific polyadenylation protein CFIm25, which is downregulated in the human seminomas. These results suggested that spindle misorientation is oncogenic, not by promoting self-renewing germ cell divisions within the niche, but by prematurely displacing proliferating cells from their normal epithelial milieu. Furthermore, they suggested RHAMM loss-of-function and spindle misorientation as an initiating event underlying both hypofertility and TGCT initiation. These findings identify spindle-associated RHAMM as an intrinsic regulator of male germ cell fate and as a gatekeeper preventing initiation of TGCTs. Cancer Res; 76(21); 6382–95. ©2016 AACR.
- Published
- 2016
- Full Text
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28. The FOS and JUN Families of Transcription Factors
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Peter E. Angel, Peter Herrlich, Peter E. Angel, and Peter Herrlich
- Subjects
- RC268.44.F67
- Abstract
This book introduces and analyzes the crucial role of AP-1 in cell growth, proliferation, differentiation, and apoptosis. AP-1 is the endpoint of several pathways of signal transduction, including one that triggers cancerous growth. The control of its activity is an issue of basic science, cancer therapy, and other diseases. The chapters provide multiple viewpoints of the emerging data on AP-1, including its role as a factor regulating genes involved in the metastatic properties of cancer, as a factor that interacts with viral gene products, and as a part of the mechanism by which steroid and retinoic acid receptors function as anti-inflammatory proteins.
- Published
- 2017
29. Novel mechanism of JNK pathway activation by adenoviral E1A
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Peter Herrlich, Valery A. Pospelov, Anna Brichkina, Vasily S. Romanov, Helen Morrison, and Tatiana V. Pospelova
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AP-1 subunit c-Jun ,Oncogene Proteins, Fusion ,MAP Kinase Signaling System ,viruses ,Immunoblotting ,RAC1 ,Biology ,Transfection ,Cell Line ,Mice ,Enzyme activator ,Downregulation and upregulation ,adenoviral E1A ,Transcription (biology) ,Animals ,Humans ,Immunoprecipitation ,Small GTPase ,RNA, Small Interfering ,Kinase ,Estrogen Receptor alpha ,Cell Transformation, Viral ,Cell biology ,Enzyme Activation ,Oncology ,NIH 3T3 Cells ,Adenovirus E1A Proteins ,Signal transduction ,JNK signaling pathway ,Estrogen receptor alpha ,Research Paper ,small GTPase Rac1 ,ERM family proteins - Abstract
// Vasily S. Romanov 1,* , Anna I. Brichkina 1,2,4,* , Helen Morrison 1 , Tatiana V. Pospelova 2,3 , Valery A. Pospelov 2,3 , Peter Herrlich 1 1 Leibniz Institute for Age Research – Fritz Lipmann Institute (FLI), Jena, Germany 2 Institute of Cytology, Russian Academy of Sciences, St. Petersburg, Russia 3 St. Petersburg State University, St. Petersburg, Russia 4 Present address: Institute of Molecular and Cell Biology, A-STAR, Proteos, Singapore * These authors contributed equally to this study Correspondence: Vasily S. Romanov, email: // Keywords : adenoviral E1A; AP-1 subunit c-Jun; JNK signaling pathway; small GTPase Rac1; ERM family proteins Received : March 5, 2014 Accepted : March 24, 2014 Published : March 25, 2014 Abstract The adenoviral oncoprotein E1A influences cellular regulation by interacting with a number of cellular proteins. In collaboration with complementary oncogenes, E1A fully transforms primary cells. As part of this action, E1A inhibits transcription of c-Jun:Fos target genes while promoting that of c-Jun:ATF2-dependent genes including jun . Both c-Jun and ATF2 are hyperphosphorylated in response to E1A. In the current study, E1A was fused with the ligand binding domain of the estrogen receptor (E1A-ER) to monitor the immediate effect of E1A activation. With this approach we now show that E1A activates c-Jun N-terminal kinase (JNK), the upstream kinases MKK4 and MKK7, as well as the small GTPase Rac1. Activation of the JNK pathway requires the N-terminal domain of E1A, and, importantly, is independent of transcription. In addition, it requires the presence of ERM proteins. Downregulation of signaling components upstream of JNK inhibits E1A-dependent JNK/c-Jun activation. Taking these findings together, we show that E1A activates the JNK/c-Jun signaling pathway upstream of Rac1 in a transcription-independent manner, demonstrating a novel mechanism of E1A action.
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- 2014
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30. The responsibility of the scientist
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Peter Herrlich
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Science history ,Science and Society ,Science ,MEDLINE ,Historical Article ,History, 19th Century ,ComputerApplications_COMPUTERSINOTHERSYSTEMS ,History, 20th Century ,Weapons of Mass Destruction ,History, 21st Century ,Biochemistry ,Harm ,Genetics ,Science ethics ,Engineering ethics ,Sociology ,Molecular Biology - Abstract
Do scientists bear the responsibility for how their research is used? What can we learn from wartime and more recent examples of how scientists have handled dual-use problems of research?
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- 2013
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31. Who decides when to cleave an ectodomain?
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Peter Herrlich, Monika Hartmann, and Andreas Herrlich
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chemistry.chemical_classification ,Metalloproteinase ,biology ,Cleavage (embryo) ,Models, Biological ,Biochemistry ,Transmembrane protein ,ADAM Proteins ,Enzyme ,chemistry ,Ectodomain ,Disintegrin ,biology.protein ,Extracellular ,Animals ,Humans ,Decoy receptors ,Molecular Biology - Abstract
Many life-essential molecules such as growth factors, cytokines, ectoenzymes, and decoy receptors are produced by ectodomain cleavage of transmembrane precursor molecules. Not surprisingly, misregulation of such essential functions is linked to numerous diseases. Ectodomain cleavage is the function of transmembrane ADAMs (a disintegrin and metalloprotease) and other membrane-bound metalloproteases, which have an extracellular catalytic domain. Almost all work on ectodomain cleavage regulation has focused on the control of enzyme activity determined by substrate cleavage as surrogate. However, the number of substrates far exceeds the number of enzymes. Specificity can therefore not be achieved by solely modulating enzyme activity. Here, we argue that specific regulatory pathways must exist to control the availability and susceptibility of substrates.
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- 2013
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32. Calpain-mediated degradation of reversibly oxidized protein-tyrosine phosphatase 1B
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Peter Herrlich, Peter A. Greer, Bernhard Schlott, Antje Trümpler, and Frank-D. Böhmer
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chemistry.chemical_classification ,Protease ,biology ,Chemistry ,medicine.medical_treatment ,Phosphatase ,Calpain ,Cell Biology ,Protein tyrosine phosphatase ,Biochemistry ,Amino acid ,Insulin receptor ,Enzyme ,medicine ,biology.protein ,Molecular Biology ,Cysteine - Abstract
Protein-tyrosine phosphatases (PTPs) are regulated by reversible inactivating oxidation of the catalytic-site cysteine. We have previously shown that reversible oxidation upon UVA irradiation is followed by calpain-mediated PTP degradation. Here, we address the mechanism of regulated cleavage and the physiological function of PTP degradation. Reversible oxidation of PTP1B in vitro strongly facilitated the association with calpain and led to greatly increased calpain-dependent inactivating cleavage. Both oxidation-induced association and cleavage depended exclusively on the presence of the catalytic (reversibly oxidized) cysteine residue 215. A major cleavage site was identified preceding amino acid position Ala77. In calpain-deficient cells, insulin signaling was apparently diminished, consistent with a possible role for calpain in removing a negative regulator of insulin signaling. Reversibly oxidized PTP1B may be a target of calpain in this context. Structured digital abstract • MINT-7234580: Calpain 4 (uniprotkb:P04632) and Calpain 1 (uniprotkb:P07384) physically interact (MI:0915) with PTP1B (uniprotkb:P18031) by enzyme linked immunosorbent assay (MI:0411) • MINT-7234562, MINT-7234481: Calpain 4 (uniprotkb:P04632) and Calpain 1 (uniprotkb:P07384) cleave (MI:0194) PTP1B (uniprotkb:P18031) by protease assay (MI:0435)
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- 2009
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33. Restriction to Fos Family Members of Trip6-Dependent Coactivation and Glucocorticoid Receptor-Dependent Trans-Repression of Activator Protein-1
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Peter Herrlich, Olivier Kassel, Sylwia Sekula, Markus E. Diefenbacher, Jana V. Maier, Margarethe Litfin, Christine Heilbock, Marc Castellazzi, and Hans van Dam
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Transcriptional Activation ,Proteasome Endopeptidase Complex ,Proto-Oncogene Proteins c-jun ,Ultraviolet Rays ,Activating transcription factor ,CREB ,Article ,Cell Line ,Mice ,Enzyme activator ,Receptors, Glucocorticoid ,Endocrinology ,Glucocorticoid receptor ,Coactivator ,Animals ,Humans ,Promoter Regions, Genetic ,Molecular Biology ,Transcription factor ,Adaptor Proteins, Signal Transducing ,LIM domain ,Activating Transcription Factor 2 ,biology ,JNK Mitogen-Activated Protein Kinases ,Dual Specificity Phosphatase 1 ,General Medicine ,LIM Domain Proteins ,Molecular biology ,Activating transcription factor 2 ,Enzyme Activation ,Repressor Proteins ,Transcription Factor AP-1 ,Enzyme Induction ,biology.protein ,ATPases Associated with Diverse Cellular Activities ,Dimerization ,Proto-Oncogene Proteins c-fos ,Protein Binding ,Transcription Factors - Abstract
The term activator protein (AP)-1 describes homodimeric and heterodimeric transcription factors composed of members of the Jun, Fos, and cAMP response element-binding protein (CREB)/activating transcription factor (ATF) families of proteins. Distinct AP-1 dimers, for instance the prototypical c-Jun:c-Fos and c-Jun:ATF2 dimers, are differentially regulated by signaling pathways and bind related yet distinct response elements in the regulatory regions of AP-1 target genes. Little is known about the dimer-specific regulation of AP-1 activity at the promoter of its target genes. We have previously shown that nTrip6, the nuclear isoform of the LIM domain protein Trip6, acts as an AP-1 coactivator. Moreover, nTrip6 is an essential component of glucocorticoid receptor (GR)-mediated trans-repression of AP-1, in that it mediates the tethering of GR to the promoter-bound AP-1. We have now discovered a striking specificity of nTrip6 actions determined by the binding preference of its LIM domains. We show that nTrip6 interacts only with Fos family members. Consequently, nTrip6 is a selective coactivator for AP-1 dimers containing Fos. nTrip6 also assembles activated GR to c-Jun:c-Fos-driven promoters. Neither nTrip6 nor GR are recruited to a promoter occupied by c-Jun:ATF2. Thus, only Fos-containing dimers are trans-repressed by GR. Thus, the dimer composition of AP-1 determines the mechanism of both the positive and negative regulation of AP-1 transcriptional activity. Interestingly, on a second level of action, GR represses the increase in transcriptional activity of c-Jun:ATF2 induced by c-Jun N-terminal kinase (JNK)-dependent phosphorylation. This repression depends on GR-mediated induction of MAPK phosphatase 1 (MKP-1) expression, which results in c-Jun N-terminal kinase inactivation.
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- 2008
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34. Supreme EnLIGHTenment: Damage Recognition and Signaling in the Mammalian UV Response
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Carsten Weiss, Michael Karin, and Peter Herrlich
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Mammals ,Light ,Ultraviolet Rays ,DNA damage ,Proteins ,Oxidation reduction ,Cell Biology ,Biology ,medicine.disease_cause ,Models, Biological ,Article ,Cell biology ,Transduction (genetics) ,Proteins metabolism ,medicine ,Animals ,Signal transduction ,Oxidation-Reduction ,Molecular Biology ,Ultraviolet ,DNA Damage ,Forecasting ,Signal Transduction - Abstract
Like their prokaryotic counterparts, mammalian cells can sense light, especially in the ultraviolet (UV) range of the spectrum. After UV exposure, cells mount an elaborate response--called the UV response--that mimics physiological signaling responses except that it targets multiple pathways, thereby lacking the defined specificity of receptor-triggered signal transduction. Despite many years of research, it is still not fully clear how UV radiation is sensed and converted into the "language of cells"--signal reception and transduction. This review focuses on how photonic energy and its primary cellular products are sensed to elicit the UV response. We are grateful to Dr. Z.Q. Wang for reading and discussing the manuscript and to F.-D. Boehmer for communicating unpublished data. C.W. is supported by the European Network of Excellence ECNIS. M.K. is an American Cancer Society Research Professor and work in his laboratory is supported by the National Institutes of Health. P.H. is supported by the Deutsche Forschungsgemeinschaft.
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- 2008
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35. Crosstalk between the glucocorticoid receptor and other transcription factors: Molecular aspects
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Olivier Kassel and Peter Herrlich
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Molecular Sequence Data ,Biology ,Cell fate determination ,Response Elements ,Biochemistry ,03 medical and health sciences ,Transduction (genetics) ,Receptors, Glucocorticoid ,0302 clinical medicine ,Endocrinology ,Glucocorticoid receptor ,Transcription (biology) ,Animals ,Humans ,Amino Acid Sequence ,Molecular Biology ,Transcription factor ,ComputingMilieux_MISCELLANEOUS ,030304 developmental biology ,Genetics ,Hormone response element ,0303 health sciences ,fungi ,Life Sciences ,Promoter ,Receptor Cross-Talk ,Cell biology ,Crosstalk (biology) ,030217 neurology & neurosurgery ,Signal Transduction ,Transcription Factors - Abstract
Glucocorticoids (GCs) regulate cell fate by altering gene expression via the glucocorticoid receptor (GR). Ligand-bound GR can activate the transcription of genes carrying the specific GR binding sequence, the glucocorticoid response element (GRE). In addition, GR can modulate, positively or negatively, directly or indirectly, the activity of other transcription factors (TFs), a process referred to as "crosstalk". In the indirect crosstalk, GR interferes with transduction pathways upstream of other TFs. In the direct crosstalk, GR and other TFs modulate each other's activity when bound to the promoters of their target genes. The multiplicity of molecular actions exerted by TFs, particularly the GR, is not only fascinating in terms of molecular structure, it also implies that the TFs participate in a wide range of regulatory processes, broader than anticipated. This review focuses on the molecular mechanisms involved in the crosstalk, on both current ideas and unresolved questions, and discusses the possible significance of the crosstalk for the physiologic and therapeutic actions of GCs.
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- 2007
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36. Hepatocyte Growth Factor-induced Ras Activation Requires ERM Proteins Linked to Both CD44v6 and F-Actin
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Helmut Ponta, Thor Kastilan, Giuseppina Pace, Véronique Orian-Rousseau, Alexandra Matzke, Peter Herrlich, and Helen Morrison
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Moesin ,macromolecular substances ,Biology ,Proto-Oncogene Proteins p21(ras) ,Ezrin ,Radixin ,Anti-apoptotic Ras signalling cascade ,Animals ,Humans ,Molecular Biology ,Cytoskeleton ,Glycoproteins ,Hepatocyte Growth Factor ,Microfilament Proteins ,Membrane Proteins ,Articles ,Cell Biology ,Proto-Oncogene Proteins c-met ,Actin cytoskeleton ,Actins ,Protein Structure, Tertiary ,Rats ,Cell biology ,Cytoskeletal Proteins ,Protein Transport ,Hyaluronan Receptors ,Son of Sevenless Proteins ,Guanine nucleotide exchange factor ,HT29 Cells ,Protein Binding ,Signal Transduction - Abstract
In several types of cells, the activation of the receptor tyrosine kinase c-Met by its ligand hepatocyte growth factor (HGF) requires the coreceptor CD44v6. The CD44 extracellular domain is necessary for c-Met autophosphorylation, whereas the intracellular domain is required for signal transduction. We have already shown that the CD44 cytoplasmic tail recruits ezrin, radixin and moesin (ERM) proteins to the complex of CD44v6, c-Met, and HGF. We have now defined the function of the ERM proteins and the step they promote in the signaling cascade. The association of ERM proteins to the coreceptor is absolutely required to mediate the HGF-dependent activation of Ras by the guanine nucleotide exchange factor Sos. The ERM proteins need, in addition, to be linked to the actin cytoskeleton to catalyze the activation of Ras. Thus, we describe here a new function of the cytoskeleton. It is part of a “signalosome” complex that organizes the activation of Ras by Sos. So far the cytoskeleton has mainly been identified as a “responder” to signal transduction. Here, we show now that F-actin acts as an “inducer” that actively organizes the signaling cascade.
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- 2007
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37. Growth factor and co-receptor release by structural regulation of substrate metalloprotease accessibility
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Monika Hartmann, Andreas Herrlich, Junzhi Ma, Liseth M. Parra, Peter Herrlich, and Salome Schubach
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0301 basic medicine ,Co-receptor ,medicine.medical_treatment ,Neuregulin-1 ,medicine.disease_cause ,Article ,Substrate Specificity ,03 medical and health sciences ,Mice ,Protein Domains ,medicine ,Animals ,Metalloproteinase ,Mutation ,Multidisciplinary ,Chymotrypsin ,030102 biochemistry & molecular biology ,biology ,Chemistry ,Chimera ,Growth factor ,Substrate (chemistry) ,Trypsin ,Cell biology ,carbohydrates (lipids) ,ADAM Proteins ,030104 developmental biology ,Hyaluronan Receptors ,Ectodomain ,biology.protein ,NIH 3T3 Cells ,medicine.drug ,Peptide Hydrolases - Abstract
Release of cytokines, growth factors and other life-essential molecules from precursors by a-disintegrin-and-metalloproteases (ADAMs) is regulated with high substrate-specificity. We hypothesized that this is achieved by cleavage-regulatory intracellular-domain (ICD)-modifications of the precursors. We show here that cleavage-stimuli-induced specific ICD-modifications cause structural substrate changes that enhance ectodomain sensitivity of neuregulin-1 (NRG1; epidermal-growth-factor) or CD44 (receptor-tyrosine-kinase (RTK) co-receptor) to chymotrypsin/trypsin or soluble ADAM. This inside-out signal transfer required substrate homodimerization and was prevented by cleavage-inhibitory ICD-mutations. In chimeras, regulation could be conferred to a foreign ectodomain, suggesting a common higher-order structure. We predict that substrate-specific protease-accessibility-regulation controls release of numerous ADAM substrates.
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- 2015
38. RHAMM deficiency disrupts folliculogenesis resulting in female hypofertility
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Anne Winkler, Heike Heuer, Jürgen Moll, Huaibiao Li, Peter Herrlich, Aspasia Ploubidou, Lucien Frappart, Stéphane Brunet, Torsten Kroll, Marie-Hélène Verlhac, Jana Hamann, Institut de biologie et chimie des protéines [Lyon] (IBCP), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Annecy-le-Vieux de Physique Théorique (LAPTH), and Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)
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Gametogenesis ,Oriented mitosis ,RHAMM ,Centrosome ,Folliculogenesis ,Hypofertility ,Spindle ,endocrine system ,Somatic cell ,QH301-705.5 ,Science ,[SDV.BC.BC]Life Sciences [q-bio]/Cellular Biology/Subcellular Processes [q-bio.SC] ,Biology ,Oogenesis ,General Biochemistry, Genetics and Molecular Biology ,Extracellular matrix ,03 medical and health sciences ,0302 clinical medicine ,Meiosis ,medicine ,Biology (General) ,Computer science, information & general works ,ComputingMilieux_MISCELLANEOUS ,030304 developmental biology ,0303 health sciences ,Oocyte ,Spindle apparatus ,Cell biology ,medicine.anatomical_structure ,030220 oncology & carcinogenesis ,Immunology ,ddc:000 ,General Agricultural and Biological Sciences ,Research Article - Abstract
The postnatal mammalian ovary contains the primary follicles, each comprising an immature oocyte surrounded by a layer of somatic granulosa cells. Oocytes reach meiotic and developmental competence via folliculogenesis. During this process, the granulosa cells proliferate massively around the oocyte, form an extensive extracellular matrix (ECM) and differentiate into cumulus cells. As the ECM component hyaluronic acid (HA) is thought to form the backbone of the oocyte-granulosa cell complex, we deleted the relevant domain of the Receptor for HA Mediated Motility (RHAMM) gene in the mouse. This resulted in folliculogenesis defects and female hypofertility, although HA-induced signalling was not affected. We report that wild-type RHAMM localises at the mitotic spindle of granulosa cells, surrounding the oocyte. Deletion of the RHAMM C-terminus in vivo abolishes its spindle association, resulting in impaired spindle orientation in the dividing granulosa cells, folliculogenesis defects and subsequent female hypofertility. These data reveal the first identified physiological function for RHAMM, during oogenesis, and the importance of this spindle-associated function for female fertility.
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- 2015
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39. Tumor Suppressor NF2 Blocks Cellular Migration by Inhibiting Ectodomain Cleavage of CD44
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Yong Li, Anne Ruschel, Liseth M. Parra, Peter Herrlich, Monika Hartmann, Helen Morrison, Andreas Herrlich, and Sandra Böhme
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Cancer Research ,medicine.medical_treatment ,Moesin ,Mice, Transgenic ,Biology ,Cleavage (embryo) ,Mice ,Ezrin ,Radixin ,Cell Movement ,medicine ,Tumor Cells, Cultured ,Animals ,Humans ,Molecular Biology ,Cells, Cultured ,Cell Proliferation ,Cleavage stimulation factor ,Neurofibromin 2 ,Growth factor ,Fibroblasts ,Actin cytoskeleton ,Molecular biology ,Cell biology ,Hyaluronan Receptors ,Oncology ,Ectodomain ,NIH 3T3 Cells - Abstract
Ectodomain cleavage (shedding) of transmembrane proteins by metalloproteases (MMP) generates numerous essential signaling molecules, but its regulation is not totally understood. CD44, a cleaved transmembrane glycoprotein, exerts both antiproliferative or tumor-promoting functions, but whether proteolysis is required for this is not certain. CD44-mediated contact inhibition and cellular proliferation are regulated by counteracting CD44 C-terminal interacting proteins, the tumor suppressor protein merlin (NF2) and ERM proteins (ezrin, radixin, moesin). We show here that activation or overexpression of constitutively active merlin or downregulation of ERMs inhibited 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced [as well as serum, hepatocyte growth factor (HGF), or platelet-derived growth factor (PDGF)] CD44 cleavage by the metalloprotease ADAM10, whereas overexpressed ERM proteins promoted cleavage. Merlin- and ERM-modulated Ras or Rac activity was not required for this function. However, latrunculin (an actin-disrupting toxin) or an ezrin mutant which is unable to link CD44 to actin, inhibited CD44 cleavage, identifying a cytoskeletal C-terminal link as essential for induced CD44 cleavage. Cellular migration, an important tumor property, depended on CD44 and its cleavage and was inhibited by merlin. These data reveal a novel function of merlin and suggest that CD44 cleavage products play a tumor-promoting role. Neuregulin, an EGF ligand released by ADAM17 from its pro-form NRG1, is predominantly involved in regulating cellular differentiation. In contrast to CD44, release of neuregulin from its pro-form was not regulated by merlin or ERM proteins. Disruption of the actin cytoskeleton however, also inhibited NRG1 cleavage. This current study presents one of the first examples of substrate-selective cleavage regulation. Implications: Investigating transmembrane protein cleavage and their regulatory pathways have provided new molecular insight into their important role in cancer formation and possible treatment. Mol Cancer Res; 13(5); 879–90. ©2015 AACR.
- Published
- 2015
40. CD44 Acts Both as a Growth- and Invasiveness-Promoting Molecule and as a Tumor-Suppressing Cofactor
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Susanne Weg-Remers, Harald König, Véronique Orian-Rousseau, Jonathan P. Sleeman, Peter Herrlich, Helen Morrison, and Helmut Ponta
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General Neuroscience ,Contact inhibition ,Biology ,medicine.disease_cause ,General Biochemistry, Genetics and Molecular Biology ,Transmembrane protein ,Cell biology ,Gene Expression Regulation, Neoplastic ,Merlin (protein) ,Hyaluronan Receptors ,Ezrin ,History and Philosophy of Science ,Neoplasms ,medicine ,Humans ,Genes, Tumor Suppressor ,Neoplasm Invasiveness ,Mode of action ,Cytoskeleton ,Carcinogenesis ,Receptor - Abstract
High-molecular-weight splice variants of the CD44 transmembrane protein family have been implicated in tumorigenesis and metastasis formation. By contrast, in certain tumors--for example, Burkitt's lymphoma, neuroblastomas, and prostate cancer--loss of CD44 expression seems to accompany transformation. Here we describe two modes of action of CD44 proteins. They can bind growth factors and present them to their authentic high-affinity receptors, and thus promote proliferation and invasiveness of cells. Under these conditions the CD44 proteins recruit ERM proteins--for example, ezrin or moesin--to their cytoplasmic tails, thereby producing links to the cytoskeleton. This mode of action could account for the tumor-promoting action of CD44 proteins. The second mode of action of CD44 proteins comes into play when cells reach confluent growth conditions. Under specific conditions, binding of another ligand, the ECM component hyaluronate, leads to the activation and binding to the CD44 cytoplasmic tail of the tumor suppressor protein merlin. The activation of merlin confers growth arrest, so-called contact inhibition. This function of CD44 proteins defines them as tumor suppressors. The type of action of CD44 on a given cell will depend on the isoform pattern of CD44 expressed, on the cellular equipment with ERM protein members, on the nature of the ECM, and on yet-unknown conditions.
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- 2006
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41. A Five-Amino-Acid Peptide Blocks Met- and Ron-Dependent Cell Migration
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Alexandra Matzke, Peter Herrlich, Helmut Ponta, and Véronique Orian-Rousseau
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Gene isoform ,Cancer Research ,Molecular Sequence Data ,Peptide ,Receptor tyrosine kinase ,Structure-Activity Relationship ,Cell Movement ,Proto-Oncogene Proteins ,Animals ,Humans ,Receptors, Growth Factor ,Amino Acid Sequence ,Receptor ,Peptide sequence ,Glycoproteins ,chemistry.chemical_classification ,biology ,CD44 ,Receptor Protein-Tyrosine Kinases ,Proto-Oncogene Proteins c-met ,Peptide Fragments ,Rats ,Amino acid ,Hyaluronan Receptors ,Oncology ,Biochemistry ,chemistry ,biology.protein ,HT29 Cells - Abstract
Various human cancers express elevated levels of the receptor tyrosine kinases Met or Ron and v6-containing isoforms of CD44. The activation of Met and Ron requires the presence of such CD44 v6-containing isoforms that act as coreceptors. Three amino acids within the v6 sequence were identified by mutational analysis to be essential for the coreceptor function: EWQ in the rat sequence and RWH in human. Peptides comprising these three amino acids (the smallest containing only five amino acids) efficiently act as competitors and block ligand-dependent activation of Met or Ron and subsequent cell migration.
- Published
- 2005
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42. Investigation of protein-tyrosine phosphatases by in-gel assays
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Peter Herrlich, Frank-D. Böhmer, Boyka Markova, and Pawan Gulati
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Gel electrophoresis ,animal structures ,Phosphatase ,Cell ,Substrate (chemistry) ,Protein tyrosine phosphatase ,Biology ,General Biochemistry, Genetics and Molecular Biology ,ErbB Receptors ,Receptor, Platelet-Derived Growth Factor beta ,medicine.anatomical_structure ,Biochemistry ,medicine ,Electrophoresis, Polyacrylamide Gel ,Protein Tyrosine Phosphatases ,Peptides ,Oxidation-Reduction ,Phosphorus Radioisotopes ,Molecular Biology ,Macromolecule - Abstract
Renaturation permits the detection of protein-tyrosine phosphatase (PTP) activities subsequent to separation by SDS–PAGE in the presence of the 32P-labeled poly(Glu4Tyr) as a macromolecular substrate. An efficient corresponding method has been developed by Burridge and Nelson [Anal. Biochem. 232 (1995) 56]. We describe here the modification of the basic method, its extension to two-dimensional gel electrophoresis, and applications to identify PTPs in signaling complexes and reversibly oxidized PTPs. Particular attention is given to the preparation of samples, to interpretation of the results as well as to advantages and limitations of the technique. Immunodepletion and the use of cells from knockout animals have been successful in the identification of individual PTPs. Readily detectable in cell lysates are PTP-PEST, SHP-2, SHP-1, PTP1B, and T-cell PTP. A much greater complexity of activity bands is, to a large extent, due to the generation of active fragments of PTPs. In-gel detection of PTPs can be employed to monitor cell fractionations and potential PTP activity changes.
- Published
- 2005
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43. Genes upregulated in a metastasizing human colon carcinoma cell line
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Véronique Orian-Rousseau, Harm HogenEsch, Wolf Gerolf Thies, Helmut Ponta, Martin Hofmann, Jörg Mengwasser, Feng Guo, Peter Herrlich, Sigrun Mink, and Publica
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Cancer Research ,Pathology ,medicine.medical_specialty ,Mice, SCID ,In situ hybridization ,Biology ,Metastasis ,Mice ,Downregulation and upregulation ,Gene expression ,Tumor Cells, Cultured ,medicine ,Animals ,Humans ,RNA, Messenger ,Gene ,Oligonucleotide Array Sequence Analysis ,Gene Expression Profiling ,Nucleic Acid Hybridization ,Cancer ,Blotting, Northern ,medicine.disease ,Neoplasm Proteins ,Up-Regulation ,Gene Expression Regulation, Neoplastic ,Oncology ,Cell culture ,Suppression subtractive hybridization ,Lymphatic Metastasis ,Subtraction Technique ,Colonic Neoplasms ,Cancer research - Abstract
Differential gene expression between the metastatic human colon cancer cell line HT29p and its nonmetastatic counterpart HT29-MTX was revealed by suppression subtractive hybridization. Fifty-eight individual genes showed increased mRNA levels in HT29p cells. Only 15 of these genes had been related to transformation in previous studies; the majority of genes are new candidates encoding proteins relevant for the metastatic process. Cancer profiling arrays as well as in situ hybridization study revealed that at least some of the genes obtained in the SSH screen are also differentially expressed in human tumors.
- Published
- 2004
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44. Antagonistic Signaling Pathways Regulate Alternative Splicing of CD44 in T Cells
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Peter Herrlich, Susanne Weg-Remers, Helmut Ponta, and Harald König
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rho GTP-Binding Proteins ,biology ,T-Lymphocytes ,General Neuroscience ,Alternative splicing ,CD44 ,Genetic Variation ,Transfection ,General Biochemistry, Genetics and Molecular Biology ,Cell biology ,Alternative Splicing ,Hyaluronan Receptors ,History and Philosophy of Science ,Genes, Reporter ,Hes3 signaling axis ,Mitogen-activated protein kinase ,biology.protein ,Humans ,Signal transduction ,Signal Transduction - Published
- 2002
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45. Inside-out Regulation of Ectodomain Cleavage of Cluster-of-Differentiation-44 (CD44) and of Neuregulin-1 Requires Substrate Dimerization
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Monika Hartmann, Andreas Herrlich, Helen Morrison, Peter Herrlich, Liseth M. Parra, Anne Ruschel, and Christina Lindner
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Cleavage factor ,Neuregulin-1 ,Recombinant Fusion Proteins ,ADAM17 Protein ,Cleavage (embryo) ,Biochemistry ,Models, Biological ,Substrate Specificity ,ADAM10 Protein ,Mice ,Cell Line, Tumor ,Extracellular ,Animals ,Humans ,Neuregulin 1 ,Molecular Biology ,Cells, Cultured ,Mice, Knockout ,biology ,Cell Membrane ,ezrin ,metalloprotease ,angiotensin ,actin ,adhesion molecule ,ADAM ,ADAM10 ,neuregulin ,ADAM17 ,Membrane Proteins ,Cell Biology ,Transmembrane protein ,Cell biology ,Protein Structure, Tertiary ,Rats ,ADAM Proteins ,HEK293 Cells ,Hyaluronan Receptors ,Ectodomain ,Cytoplasm ,Proteolysis ,biology.protein ,Mutagenesis, Site-Directed ,NIH 3T3 Cells ,Cattle ,Amyloid Precursor Protein Secretases ,Protein Multimerization ,Intracellular ,Signal Transduction - Abstract
Ectodomain shedding of transmembrane precursor proteins generates numerous life-essential molecules, such as epidermal growth factor receptor ligands. This cleavage not only releases the regulatory growth factor, but it is also the required first step for the subsequent processing by γ-secretase and the release of gene regulatory intracellular fragments. Signaling within the cell modifies the cytoplasmic tails of substrates, a step important in starting the specific and regulated cleavage of a large number of studied substrates. Ectodomain cleavage occurs, however, on the outside of the plasma membrane and is carried out by membrane-bound metalloproteases. How the intracellular domain modification communicates with the ectodomain of the substrate to allow for cleavage to occur is unknown. Here, we show that homodimerization of a cluster-of-differentiation-44 or of pro-neuregulin-1 monomers represents an essential pre-condition for their regulated ectodomain cleavage. Both substrates are associated with their respective metalloproteases under both basal or cleavage-stimulated conditions. These interactions only turn productive by specific intracellular signal-induced intracellular domain modifications of the substrates, which in turn regulate metalloprotease access to the substrates' ectodomain and cleavage. We propose that substrate intracellular domain modification induces a relative rotation or other positional change of the dimerization partners that allow metalloprotease cleavage in the extracellular space. Our findings fill an important gap in understanding substrate-specific inside-out signal transfer along cleaved transmembrane proteins and suggest that substrate dimerization (homo- or possibly heterodimerization) might represent a general principle in ectodomain shedding.
- Published
- 2014
46. CD44-dependent lymphoma cell dissemination: a cell surface CD44 variant, rather than standard CD44, supports in vitro lymphoma cell rolling on hyaluronic acid substrate and its in vivo accumulation in the peripheral lymph nodes
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David Naor, Peter Herrlich, Shulamit B. Wallach-Dayan, Valentin Grabovsky, Jonathan P. Sleeman, Ronen Alon, and Jürgen Moll
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DNA, Complementary ,T cell ,Mice, Nude ,Lymphoma, T-Cell ,Transfection ,Mice ,Adjuvants, Immunologic ,Cell Movement ,Cell Adhesion ,Tumor Cells, Cultured ,medicine ,Lymph node stromal cell ,Animals ,Hyaluronic Acid ,Antigen-presenting cell ,Lymph node ,Mice, Inbred BALB C ,Binding Sites ,biology ,CD44 ,Cell migration ,Cell Biology ,Molecular biology ,Alternative Splicing ,Hyaluronan Receptors ,medicine.anatomical_structure ,Mutagenesis ,Antigens, Surface ,Immunology ,Cancer cell ,biology.protein ,Female ,Lymph Nodes ,Stress, Mechanical ,Lymph - Abstract
Cell motility is an essential element of tumor dissemination, allowing organ infiltration by cancer cells. Using mouse LB lymphoma cells transfected with standard CD44 (CD44s) cDNA (LB-TRs cells) or with the alternatively spliced CD44 variant CD44v4-v10 (CD44v) cDNA (LB-TRv cells), we explored their CD44-dependent cell migration. LB-TRv cells, but not LB-TRs or parental LB cells, bound soluble hyaluronic acid (HA) and other glycosaminoglycans (GAGs), and exclusively formed, under physiological shear force, rolling attachments on HA substrate. Furthermore, LB-TRv cells, but not LB-TRs cells or their parental LB cells, displayed accelerated local tumor formation and enhanced accumulation in the peripheral lymph nodes after s.c. inoculation. The aggressive metastatic behavior of i.v.-injected LB-TRV cells, when compared with that of other LB-transfectants, is attributed to more efficient migration to the lymph nodes, rather than to local growth in the lymph node. Injection of anti-CD44 monoclonal antibody or of the enzyme hyaluronidase also prevented tumor growth in lymph nodes of BALB/c mice inoculated with LB-TRv cells. The enhanced in vitro rolling and enhanced in vivo local tumor growth and lymph node invasion disappeared in LB cells transfected with CD44v cDNA bearing a point mutation at the HA binding site, located at the distal end of the molecule constant region. These findings show that the interaction of cell surface CD44v with HA promotes cell migration both in vitro and in vivo, and they contribute to our understanding of the mechanism of cell trafficking, including tumor spread.
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- 2001
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47. Regulation of alternative pre-mRNA splicing by the ERK MAP-kinase pathway
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Helmut Ponta, Susanne Weg-Remers, Peter Herrlich, and Harald König
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Cell signaling ,MAP Kinase Signaling System ,T-Lymphocytes ,MAP Kinase Kinase 2 ,MAP Kinase Kinase 1 ,Protein Serine-Threonine Kinases ,Article ,General Biochemistry, Genetics and Molecular Biology ,Proto-Oncogene Proteins p21(ras) ,Mice ,Exon ,Genes, Reporter ,RNA Precursors ,Tumor Cells, Cultured ,Animals ,Protein Isoforms ,Gene silencing ,Gene Silencing ,Luciferases ,Molecular Biology ,Cells, Cultured ,Mitogen-Activated Protein Kinase 1 ,Mitogen-Activated Protein Kinase Kinases ,Regulation of gene expression ,Mice, Inbred BALB C ,Mitogen-Activated Protein Kinase 3 ,General Immunology and Microbiology ,biology ,General Neuroscience ,Alternative splicing ,CD44 ,Exons ,Protein-Tyrosine Kinases ,Molecular biology ,Up-Regulation ,Proto-Oncogene Proteins c-raf ,Alternative Splicing ,Hyaluronan Receptors ,Gene Expression Regulation ,RNA splicing ,biology.protein ,Mitogen-Activated Protein Kinases ,Signal transduction - Abstract
Differential gene expression through alternative pre-mRNA splicing is crucial to various physiological and pathological conditions. Upon activation of B and T lymphocytes during an immune response, variant isoforms of the cell surface molecule CD44 are generated by alternative pre-mRNA splicing. We show here that in primary mouse T cells as well as in the murine LB-17 T-cell line upregulation of variant CD44 mRNA species upon T-cell activation requires activation of the MEK–ERK pathway. By employing mutant signaling molecules and a novel luciferase-based splice reporter system we demonstrate that the Ras–Raf–MEK–ERK signaling cascade, but not the p38 MAP-kinase pathway, activates a mechanism that retains variant CD44 exon v5 sequence in mature mRNA. The findings demonstrate that a highly conserved pleiotropic signaling pathway links extracellular cues to splice regulation, providing an avenue for tissue-specific, developmental or pathology-associated splicing decisions.
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- 2001
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48. The NF2 tumor suppressor gene product, merlin, mediates contact inhibition of growth through interactions with CD44
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David H. Gutmann, James Legg, Helen Morrison, Clare M. Isacke, Carrie A. Haipek, Larry S. Sherman, Peter Herrlich, Fatima Banine, and Helmut Ponta
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Time Factors ,Tumor suppressor gene ,Moesin ,Blotting, Western ,macromolecular substances ,Biology ,Ligands ,Models, Biological ,3T3 cells ,Cell Line ,Mice ,Dogs ,Ezrin ,Adjuvants, Immunologic ,Genetics ,medicine ,Animals ,Genes, Tumor Suppressor ,Hyaluronic Acid ,Phosphorylation ,Glutathione Transferase ,Glycosaminoglycans ,Neurofibromin 2 ,Cell growth ,Microfilament Proteins ,Membrane Proteins ,Contact inhibition ,3T3 Cells ,Phosphoproteins ,Molecular biology ,Extracellular Matrix ,Rats ,Merlin (protein) ,Cytoskeletal Proteins ,Hyaluronan Receptors ,medicine.anatomical_structure ,Signal transduction ,Cell Division ,Signal Transduction ,Research Paper ,Developmental Biology - Abstract
The neurofibromatosis-2 (NF2) gene encodes merlin, an ezrin-radixin-moesin-(ERM)-related protein that functions as a tumor suppressor. We found that merlin mediates contact inhibition of growth through signals from the extracellular matrix. At high cell density, merlin becomes hypo-phosphorylated and inhibits cell growth in response to hyaluronate (HA), a mucopolysaccharide that surrounds cells. Merlin's growth-inhibitory activity depends on specific interaction with the cytoplasmic tail of CD44, a transmembrane HA receptor. At low cell density, merlin is phosphorylated, growth permissive, and exists in a complex with ezrin, moesin, and CD44. These data indicate that merlin and CD44 form a molecular switch that specifies cell growth arrest or proliferation.
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- 2001
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49. Heterogeneous Ribonucleoprotein A1 Is Part of an Exon-specific Splice-silencing Complex Controlled by Oncogenic Signaling Pathways
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Harald König, Helmut Ponta, Manuela Marx, Peter Herrlich, Nathalie Matter, and Susanne Weg-Remers
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Heterogeneous Nuclear Ribonucleoprotein A1 ,RNA Splicing ,Blotting, Western ,Down-Regulation ,Oncogene Protein p21(ras) ,Biology ,Transfection ,Heterogeneous ribonucleoprotein particle ,Models, Biological ,environment and public health ,Biochemistry ,Heterogeneous-Nuclear Ribonucleoproteins ,Epitopes ,Mice ,Exon ,Two-Hybrid System Techniques ,Heterogeneous-Nuclear Ribonucleoprotein Group A-B ,Tumor Cells, Cultured ,Animals ,Humans ,Protein Isoforms ,Gene silencing ,splice ,RNA, Messenger ,cdc42 GTP-Binding Protein ,Molecular Biology ,Ribonucleoprotein ,Genetics ,Reverse Transcriptase Polymerase Chain Reaction ,Alternative splicing ,3T3 Cells ,Exons ,Cell Biology ,Cell biology ,Alternative Splicing ,Hyaluronan Receptors ,Ribonucleoproteins ,Mutagenesis ,RNA splicing ,ras Proteins ,RNA ,Signal Transduction - Abstract
Regulation of alternative pre-mRNA splicing, recognized as increasingly important in causing human disease, was studied using the CD44 gene, whose splice variants have been implicated in tumor progression. We identified heterogeneous ribonucleoprotein (hnRNP) A1 as a protein interacting in vitro and in vivo with regulatory splice elements in CD44 variant exon v5. Transient overexpression of hnRNP A1 prevented v5 exon inclusion, dependent on the exonic elements. HnRNP A1-dependent repression was exon-specific and could be relieved by coexpression of oncogenic forms of Ras and Cdc42. The results define hnRNP A1 as a decisive part of an oncogene-regulated splice-silencing complex, which can select between multiple alternatively spliced exons.
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- 2000
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50. The CD44 Receptor of Lymphoma Cells: Structure-Function Relationships and Mechanism of Activation
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Dvorah Ish-Shalom, Ronit Vogt Sionov, Shulamit Batya Wallach, Jürgen Moll, David Naor, Itshak Golan, Mark Rochman, Peter Herrlich, and Shlomo Nedvetzki
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Glycosylation ,Cell ,Neuraminidase ,Biology ,Lymphoma, T-Cell ,Microfilament ,Mice ,Structure-Activity Relationship ,chemistry.chemical_compound ,Microtubule ,Tumor Cells, Cultured ,medicine ,Animals ,Hyaluronic Acid ,Cytoskeleton ,Receptor ,DNA Primers ,Mice, Inbred BALB C ,Reverse Transcriptase Polymerase Chain Reaction ,Cell adhesion molecule ,Tunicamycin ,CD44 ,Drug Synergism ,General Medicine ,Flow Cytometry ,N-Acetylneuraminic Acid ,Anti-Bacterial Agents ,Up-Regulation ,Cell biology ,Hyaluronan Receptors ,medicine.anatomical_structure ,chemistry ,Antigens, Surface ,Carcinogens ,biology.protein ,Phorbol ,Tetradecanoylphorbol Acetate - Abstract
Migration of some tumor cells, and their lodgment in target organs, is dependent on the activation of cell surface CD44 receptor, usually detected by its ability to bind hyaluronic acid (HA) or other ligands. In an attempt to reveal the mechanism of tumor cell CD44 activation, we compared the physical and chemical properties of CD44 in nonactivated LB cell lymphoma with those in phorbol 12-myristate 13-acetate (PMA)-activated LB cells and of an LB cell subline (designated HA9) expressing constitutively-active CD44. In contrast to nonactivated LB cells, PMA-activated LB cells and HA9 cells displayed a CD44-dependent ability to bind HA. The ability of activated cell CD44 to bind HA was not dependent on microfilament or microtubule integrity or on changes in CD44 mobility on the membrane plane, indicating that the CD44 activation status is not associated with cytoskeleton function. Aside from the increased expression of CD44 on the surface of PMA-activated LB cells and HA9 cells, qualitative differences between the CD44 of nonactivated and activated LB cells were also detected: the CD44 of the activated lymphoma was (i) larger in molecular size, (ii) displayed a broader CD44 isoform repertoire, including a CD44 variant that binds HA, and (iii) its glycoprotein contained less sialic acid. Indeed, after removal of sialic acid from their cell surface by neuraminidase, LB cells acquired the ability to bind HA. However, a reduced dose of neuraminidase did not confer HA binding on LB cells, unless they were also activated by a low concentration of PMA, which by itself was ineffective. Similarly, under suboptimal conditions, a synergistic effect was obtained with tunicamycin and PMA: each one alone was ineffective but in combination they induced the acquisition of HA binding by the lymphoma cells, while their CD44 expression was not enhanced. Unveiling of the activation mechanism of CD44, by exposing the cells to PMA stimulation or to deglycosylation, is not only academically important, but it also has practical implications, as activated CD44 may be involved in the support of tumor progression.
- Published
- 2000
- Full Text
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