References of "Twizere, Jean-Claude"
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See detailUnveiling of a new role for DPF3 protein in cancer biology
Verrillo, Giulia ULiege; Hanache, Sarah ULiege; Duchemin, Amandine ULiege et al

Poster (2019, February)

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See detailVaricella Zoster Virus ORF9p binding to cellular adaptor protein complex-1 is important for viral infectivity.
Lebrun, Marielle ULiege; Lambert, Julien ULiege; Riva, Laura et al

in Journal of Virology (2018), 92(15),

ORF9p (homologous to HSV-1 VP22) is a varicella-zoster virus (VZV) tegument protein essential for viral replication. Even though its precise functions are far from being fully described, a role in the ... [more ▼]

ORF9p (homologous to HSV-1 VP22) is a varicella-zoster virus (VZV) tegument protein essential for viral replication. Even though its precise functions are far from being fully described, a role in the secondary envelopment of the virus has long been suggested. We performed a yeast two-hybrid screen to identify cellular proteins interacting with ORF9p that might be important for this function. We found thirty-one ORF9p interaction partners, among which AP1M1, the mu subunit of the adaptor protein complex-1 (AP-1). AP-1 is a heterotetramer involved in intracellular vesicle-mediated transport and regulates the shuttling of cargo proteins between endosomes and the TGN via clathrin-coated vesicles. We confirmed that AP-1 interacts with ORF9p in infected cells and mapped potential interaction motifs within ORF9p. We generated VZV mutants in which each of these motifs is individually impaired and identified leucine 231 in ORF9p as critical to interact with AP-1. Disrupting ORF9p binding to AP-1 by mutating leucine 231 to alanine in ORF9p strongly impaired viral growth, most likely by preventing efficient secondary envelopment of the virus. Leucine 231 is part of a di-leucine motif conserved among alphaherpesviruses and we showed that VP22 of MDV and HSV-2 also interact with AP-1. This indicates that the function of this interaction in the secondary envelopment might be conserved as well.IMPORTANCE Herpesviruses are responsible for infections that, especially in immunocompromised patients, can lead to severe complications, including neurological symptoms and strokes. The constant emergence of viral strains resistant to classical antivirals (mainly acyclovir and its derivatives) pleads for the identification of new targets for future antiviral treatments. Cellular adaptor protein complexes (AP) have been implicated in the correct addressing of herpesvirus glycoproteins in infected cells and the discovery that a major constituent of varicella-zoster virus tegument is interacting with AP-1 reveals a previously unsuspected role of this tegument protein. Unraveling the complex mechanisms leading to virion production will certainly be an important step in the discovery of future therapeutic targets. [less ▲]

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See detailDeciphering the radiosensitivity of HPV-positive tumors
Bruyère, Diane ULiege; Lebeau, Alizée ULiege; RONCARATI, Patrick ULiege et al

Poster (2018, May 30)

The increased radiosensitivity of HPV positive tumors (compared to HPV negative ones) is widely known in clinical settings. However, the mechanisms by which this phenomenon occurs are still to be ... [more ▼]

The increased radiosensitivity of HPV positive tumors (compared to HPV negative ones) is widely known in clinical settings. However, the mechanisms by which this phenomenon occurs are still to be elucidated. A few hypotheses have been suggested regarding this differential radiosensitivity like, for example, an altered microtumoral environment or virus-host protein interactions. In this study, we focused on interactions between DNA repair proteins and virus oncoproteins. A large panel of 147 proteins implicated in DNA repair pathways was tested for potential interaction with HPV16 E6 and/or E7 oncoproteins using the GPCA method (Gaussia Princeps Complementation Assay). The proteins highlighted by the screening were validated by co-IP. The functional experiments, realized on HPV negative head and neck cancer (UPCI-SCC-111, FaDu, UPCI-SCC-40), vulva cancer (C33a) and control keratinocytes (HaCaT) stably transduced with E6 and/or E7, are in progress. [less ▲]

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See detailDeciphering the radiosensitivity of HPV-positive tumors
Bruyère, Diane ULiege; Lebeau, Alizée ULiege; RONCARATI, Patrick ULiege et al

Poster (2018, May 28)

The increased radiosensitivity of HPV positive tumors (compared to HPV negative ones) is widely known in clinical settings. However, the mechanisms by which this phenomenon occurs are still to be ... [more ▼]

The increased radiosensitivity of HPV positive tumors (compared to HPV negative ones) is widely known in clinical settings. However, the mechanisms by which this phenomenon occurs are still to be elucidated. A few hypotheses have been suggested regarding this differential radiosensitivity like, for example, an altered microtumoral environment or virus-host protein interactions. In this study, we focused on interactions between DNA repair proteins and virus oncoproteins. A large panel of 147 proteins implicated in DNA repair pathways was tested for potential interaction with HPV16 E6 and/or E7 oncoproteins using the GPCA method (Gaussia Princeps Complementation Assay). The proteins highlighted by the screening were validated by co-IP. The functional experiments, realized on HPV negative head and neck cancer (UPCI-SCC-111, FaDu, UPCI-SCC-40), vulva cancer (C33a) and control keratinocytes (HaCaT) stably transduced with E6 and/or E7, are in progress. [less ▲]

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See detailUnveiling a New Role of DPF3 Protein in Cancer Biology
Verrillo, Giulia ULiege; Hanache, Sarah; Duchemin, Amandine ULiege et al

Poster (2018, February 01)

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See detailMale-specific epistasis between WWC1 and TLN2 genes is associated with Alzheimer's disease.
Gusareva, Elena S.; Twizere, Jean-Claude ULiege; Sleegers, Kristel et al

in Neurobiology of Aging (2018), 72

Systematic epistasis analyses in multifactorial disorders are an important step to better characterize complex genetic risk structures. We conducted a hypothesis-free sex-stratified genome-wide screening ... [more ▼]

Systematic epistasis analyses in multifactorial disorders are an important step to better characterize complex genetic risk structures. We conducted a hypothesis-free sex-stratified genome-wide screening for epistasis contributing to Alzheimer's disease (AD) susceptibility. We identified a statistical epistasis signal between the single nucleotide polymorphisms rs3733980 and rs7175766 that was associated with AD in males (genome-wide significant pBonferroni-corrected=0.0165). This signal pointed toward the genes WW and C2 domain containing 1, aka KIBRA; 5q34 and TLN2 (talin 2; 15q22.2). Gene-based meta-analysis in 3 independent consortium data sets confirmed the identified interaction: the most significant (pmeta-Bonferroni-corrected=9.02*10(-3)) was for the single nucleotide polymorphism pair rs1477307 and rs4077746. In functional studies, WW and C2 domain containing 1, aka KIBRA and TLN2 coexpressed in the temporal cortex brain tissue of AD subjects (beta=0.17, 95% CI 0.04 to 0.30, p=0.01); modulated Tau toxicity in Drosophila eye experiments; colocalized in brain tissue cells, N2a neuroblastoma, and HeLa cell lines; and coimmunoprecipitated both in brain tissue and HEK293 cells. Our finding points toward new AD-related pathways and provides clues toward novel medical targets for the cure of AD. [less ▲]

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See detailAnalysis of Genes Associated With Monogenic Primary Immunodeficiency Identifies Rare Variants in XIAP in Patients With Crohn's Disease.
Amininejad, Leila; Charloteaux, Benoît ULiege; Theatre, Emilie ULiege et al

in Gastroenterology (2018), 154(8), 2165-2177

BACKGROUND & AIMS: A few rare monogenic primary immunodeficiencies (PIDs) are characterized by chronic intestinal inflammation that resembles Crohn's disease (CD). We investigated whether 23 genes ... [more ▼]

BACKGROUND & AIMS: A few rare monogenic primary immunodeficiencies (PIDs) are characterized by chronic intestinal inflammation that resembles Crohn's disease (CD). We investigated whether 23 genes associated with 10 of these monogenic disorders contain common, low-frequency, or rare variants that increase risk for CD. METHODS: Common and low frequency variants in 1 Mb loci centered on the candidate genes were analyzed using meta-data corresponding to genotypes of approximately 17,000 patients with CD or without CD (controls) in Europe. The contribution of rare variants was assessed by high-throughput sequencing of 4750 individuals, including 660 early-onset and/or familial cases among the 2390 patients with CD. Variants were expressed from vectors in SW480 or HeLa cells and functions of their products were analyzed in immunofluorescence, luciferase, immunoprecipitation, and immunoblot assays. RESULTS: We reproduced the association of the interleukin 10 locus with CD (P = .007), although none of the significantly associated variants modified the coding sequence of interleukin 10. We found XIAP to be significantly enriched for rare coding mutations in patients with CD vs controls (P = .02). We identified 4 previously unreported missense variants associated with CD. Variants in XIAP cause the PID X-linked lymphoproliferative disease type 2, yet none of the carriers of these variants had all the clinical features of X-linked lymphoproliferative disease type 2. Identified XIAP variants S123N, R233Q, and P257A were associated with an impaired activation of NOD2 signaling after muramyl dipeptide stimulation. CONCLUSIONS: In a systematic analysis of variants in 23 PID-associated genes, we confirmed the association of variants in XIAP with CD. Further screenings for CD-associated variants and analyses of their functions could increase our understanding of the relationship between PID-associated genes and CD pathogenesis. [less ▲]

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See detailActivation of the orphan G protein-coupled receptor GPR27 by surrogate ligands promotes β-arrestin 2 recruitment
Dupuis, Nadine ULiege; Laschet, Céline ULiege; Franssen, Delphine ULiege et al

in Molecular Pharmacology (2017), 91(6), 595-608

G protein-coupled receptors are the most important drug targets for human diseases. An important number of them remain devoid of confirmed ligands. GPR27 is one of these orphan receptors, characterized by ... [more ▼]

G protein-coupled receptors are the most important drug targets for human diseases. An important number of them remain devoid of confirmed ligands. GPR27 is one of these orphan receptors, characterized by a high level of conservation among vertebrates and a predominant expression in the central nervous system. In addition, it has recently been linked to insulin secretion. However, the absence of endogenous or surrogate ligands for GPR27 complicates the examination of its biological function. Our aim was to validate GPR27 signaling pathways and therefore we sought to screen a diversity oriented synthesis library to identify GPR27-specific surrogate agonists. In order to select an optimal screening assay, we investigated GPR27 ligand-independent activity. Both in G protein-mediated pathways and in β-arrestin 2 recruitment, no ligand-independent activity could be measured. However, we observed a recruitment of β-arrestin 2 to a GPR27V2 chimera in the presence of membrane-anchored β-adrenergic receptor kinase 1 (GRK2). Therefore, we optimized a firefly luciferase complementation assay to screen against this chimeric receptor. We identified two compounds (N-[4-(anilinocarbonyl)phenyl]-2,4-dichlorobenzamide (ChemBridge ID5128535) and 2,4-dichloro-N-{4-[(1,3-thiazol-2-ylamino)sulfonyl]phenyl}benzamide (ChemBridge ID5217941)) sharing a N-phenyl-2,4-dichlorobenzamide scaffold, which were selective for GPR27 over its closely related family members GPR85 and GPR173. The specificity of the activity was confirmed with a NanoBiT® β-arrestin 2 assay, imaging of GFP-tagged β-arrestin 2 and PathHunter® β-arrestin 2 Assay. Interestingly, no G protein activation was detected upon activation of GPR27 by these compounds. Our study provides the first selective surrogate agonists for the orphan GPR27. [less ▲]

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See detailUnveiling a New Role of DPF3 Protein in Cancer Biology
Verrillo, Giulia ULiege; Hanache, Sarah; Duchemin, Amandine ULiege et al

Poster (2017, May 11)

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See detailUnravelling Potential Roles of HTLV-1 Tax and HBZ Proteins in mRNA Splicing Regulation
Vandermeulen, Charlotte ULiege; Cherkaoui, Majid ULiege; Calderwood, Michael A. et al

Poster (2017, March 08)

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See detailUnveiling a New Role of DPF3 Protein in Cancer Biology
Verrillo, Giulia ULiege; Duchemin, Amandine ULiege; Hanache, Sarah et al

Poster (2017, February 01)

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See detailSmall molecule ligands for the orphan GPR27
Dupuis, Nadine ULiege; Franssen, Delphine ULiege; Laschet, Céline ULiege et al

Poster (2016, September 26)

Background G protein-coupled receptors (GPCRs) are involved in many physiological processes and constitute the target of around 30% of marketed therapies. Nonetheless, ~100 human GPCRs have no known ... [more ▼]

Background G protein-coupled receptors (GPCRs) are involved in many physiological processes and constitute the target of around 30% of marketed therapies. Nonetheless, ~100 human GPCRs have no known ligand and are designated as "orphan". This project focuses on GPR27, a rhodopsin-like alpha orphan of the SREB family (Super conserved Receptors Expressed in the Brain), presumably involved in the regulation of insulin secretion [1]. Methods In order to identify small molecules activating GPR27, we developed a firefly luciferase complementation assay (based on [2]) to assess the binding of ß-arrestin2 to the activated GPCR. To increase the affinity for and strengthen the interaction with ß-arrestin2, a GPR27-V2R chimera has been used for library screening. Results Small molecules activating GPR27-V2 have been identified in the DiverSetTM library (ChemBridge). After exclusion of non-specific activities using another unrelated GPCR, two compounds sharing a common scaffold with activity in the low micromolar range were selected for further investigations. We confirmed their agonist profile by performing complete concentration-response curves on our arrestin complementation assay as well as orthogonal assays. These compounds show good specificity being inactive on GPR85-V2 and GPR173-V2 (the two other SREB members). With these original tools, we characterized the recruitment of ß-arrestin2 to activated GPR27 WT. Conclusion We identified small molecule ligands for GPR27 that will serve as valuable tools for studying the pharmacology of GPR27 as well as its physiological roles, for example in insulin secretion. 1 Ku G.M., Pappalardo Z., Luo C.C., German M.S., McManus M.T. An siRNA Screen in Pancreatic Beta Cells Reveals a Role for Gpr27 in Insulin Production. PLoS genetics. 2012, 8, e1002449. 2 Takakura H., Hattori M., Takeuchi M., Ozawa T. Visualization and Quantitative Analysis of G Protein-Coupled Receptor−β-Arrestin Interaction in Single Cells and Specific Organs of Living Mice Using Split Luciferase Complementation. ACS Chem. Biol. 2012, 7, 901−910. [less ▲]

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See detailRole of Varicella Zoster virus ORF9p in the secondary egress : importance of its interaction with the cellular Adaptin Protein-1.
Lebrun, Marielle ULiege; riva, laura; lambert, julien et al

Poster (2016, May 20)

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See detailIdentification of small molecule ligands for the orphan GPCR GPR27
Dupuis, Nadine ULiege; Gilissen, Julie; Derj, Anouar ULiege et al

Poster (2016, January 25)

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See detailThe transcription factor ERG recruits CCR4-NOT to control mRNA decay and mitotic progression.
Rambout, Xavier ULiege; Detiffe, Cecile; Bruyr, Jonathan et al

in Nature Structural and Molecular Biology (2016)

Control of mRNA levels, a fundamental aspect in the regulation of gene expression, is achieved through a balance between mRNA synthesis and decay. E26-related gene (Erg) proteins are canonical ... [more ▼]

Control of mRNA levels, a fundamental aspect in the regulation of gene expression, is achieved through a balance between mRNA synthesis and decay. E26-related gene (Erg) proteins are canonical transcription factors whose previously described functions are confined to the control of mRNA synthesis. Here, we report that ERG also regulates gene expression by affecting mRNA stability and identify the molecular mechanisms underlying this function in human cells. ERG is recruited to mRNAs via interaction with the RNA-binding protein RBPMS, and it promotes mRNA decay by binding CNOT2, a component of the CCR4-NOT deadenylation complex. Transcriptome-wide mRNA stability analysis revealed that ERG controls the degradation of a subset of mRNAs highly connected to Aurora signaling, whose decay during S phase is necessary for mitotic progression. Our data indicate that control of gene expression by mammalian transcription factors may follow a more complex scheme than previously anticipated, integrating mRNA synthesis and degradation. [less ▲]

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See detailSystematic interactome mapping of acute lymphoblastic leukemia cancer gene products reveals EXT-1 tumor suppressor as a Notch1 and FBWX7 common interactor.
Daakour, Sarah ULiege; Hajingabo, Leon Juvenal; Kerselidou, Despoina et al

in BMC Cancer (2016), 16(1), 335

BACKGROUND: Perturbed genotypes in cancer can now be identified by whole genome sequencing of large number of diverse tumor samples, and observed gene mutations can be used for prognosis and ... [more ▼]

BACKGROUND: Perturbed genotypes in cancer can now be identified by whole genome sequencing of large number of diverse tumor samples, and observed gene mutations can be used for prognosis and classification of cancer subtypes. Although mutations in a few causative genes are directly linked to key signaling pathways perturbation, a global understanding of how known cancer genes drive oncogenesis in human is difficult to assess. METHODS: We collected available information about mutated genes in Acute Lymphoblastic Leukemia (ALL). Validated human protein interactions (PPI) were collected from IntAct, HPRD and BioGRID interactomics databases, or obtained using yeast two-hybrid screening assay. RESULTS: We have mapped interconnections between 116 cancer census gene products associated with ALL. Combining protein-protein interactions data and cancer-specific gene mutations information, we observed that 63 ALL-gene products are interconnected and identified 37 human proteins interacting with at least 2 ALL-gene products. We highlighted exclusive and coexistence genetic alterations in key signaling pathways including the PI3K/AKT and the NOTCH pathways. We then used different cell lines and reporter assay systems to validate the involvement of EXT1 in the Notch pathway. CONCLUSION: We propose that novel ALL-gene candidates can be identified based on their functional association with well-known cancer genes. We identified EXT1, a gene not previously linked to ALL via mutations, as a common interactor of NOTCH1 and FBXW7 regulating the NOTCH pathway in an FBXW7-dependend manner. [less ▲]

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See detailIdentification of VZV ORF9p potential cellular partners that could be important for the viral egress.
Lebrun, Marielle ULiege; riva, laura; Rambout, Xavier ULiege et al

Poster (2015, July 26)

ORF9p (homologous to HSV-1 VP22) is a VZV tegument protein essential for the viral replication. During the lytic cycle it is the mostly expressed gene. We have recently demonstrated that it is a substrate ... [more ▼]

ORF9p (homologous to HSV-1 VP22) is a VZV tegument protein essential for the viral replication. During the lytic cycle it is the mostly expressed gene. We have recently demonstrated that it is a substrate of the viral kinase ORF47p and that its ORF47p-dependent phosphorylation is important for the secondary envelopment process. We also have identified an acidic cluster (AC) within the protein that is important for its correct localization in the infected cells and for the interaction with ORF47p. The recombinant VZV expressing ORF9p-ΔAC presents an accumulation of capsids in the perinuclear space. ORF9p seems then to play an important role in several steps of the egress process. In this context, we sought to identify cellular partners of ORF9p that might be important for these functions. We performed a yeast two hybrid screen against the human ORFeome 5.1. and picked out 44 candidates among which 5 proteins playing roles in membrane organization and targeting. We currently are trying to confirm these interactions in infected cells and to assess the role of these interactions for the viral lytic cycle. [less ▲]

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See detailA fungal biofilm reactor based on metal structured packing improves the quality of a Gla::GFP fusion protein produced by Aspergillus oryzae
Zune, Quentin ULiege; Delepierre, Anissa ULiege; Gofflot, Sebastien et al

in Applied Microbiology and Biotechnology (2015)

Fungal biofilm is known to promote the excretion of secondary metabolites in accordance with solid-state related physiological mechanisms. This work is based on the comparative analysis of classical ... [more ▼]

Fungal biofilm is known to promote the excretion of secondary metabolites in accordance with solid-state related physiological mechanisms. This work is based on the comparative analysis of classical submerged fermentation with a fungal biofilm reactor for the production of a Gla::GFP fusion protein by Aspergillus oryzae. The biofilm reactor comprises a metal structured packing allowing the attachment of the fungal biomass. Since the production of the target protein is under the control of the promoter glaB, specifically induced in solid-state fermentation, the biofilm mode of culture is expected to enhance the global productivity. Although production of the target protein was enhanced by using the biofilm mode of culture, we also found that fusion protein production is also significant when the submerged mode of culture is used. This result is related to high shear stress leading to biomass autolysis and leakage of intracellular fusion protein into the extracellular medium. Moreover, 2D-gel electrophoresis highlights the preservation of fusion protein integrity produced in biofilm conditions. Two fungal biofilm reactor designs were then investigated further, i.e. with full immersion of the packing or with medium recirculation on the packing, and the scale-up potentialities were evaluated. In this context, it has been shown that full immersion of the metal packing in the liquid medium during cultivation allows for a uniform colonization of the packing by the fungal biomass and leads to a better quality of the fusion protein. [less ▲]

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