Chimie, Modélisation pour la Reconnaissance des Protéines

Publications de l’équipe

Année de publication : 2020

Rahima Chennoufi, Ngoc-Duong Trinh, Françoise Simon, Guillaume Bordeau, Delphine Naud-Martin, Albert Moussaron, Bertrand Cinquin, Houcine Bougherara, Béatrice Rambaud, Patrick Tauc, Céline Frochot, Marie-Paule Teulade-Fichou, Florence Mahuteau-Betzer & Eric Deprez (2020 Apr 23)

Interplay between cellular uptake, intracellular localization and the cell death mechanism in triphenylamine-mediated photoinduced cell death

Scientific Reports : 10 : 6881 : DOI : 10.1038/s41598-020-63991-9 En savoir plus
Résumé

Triphenylamines (TPAs) were previously shown to trigger cell death under prolonged one- or two-photon illumination. Their initial subcellular localization, before prolonged illumination, is exclusively cytoplasmic and they translocate to the nucleus upon photoactivation. However, depending on their structure, they display significant differences in terms of precise initial localization and subsequent photoinduced cell death mechanism. Here, we investigated the structural features of TPAs that influence cell death by studying a series of molecules differing by the number and chemical nature of vinyl branches. All compounds triggered cell death upon one-photon excitation, however to different extents, the nature of the electron acceptor group being determinant for the overall cell death efficiency. Photobleaching susceptibility was also an important parameter for discriminating efficient/inefficient compounds in two-photon experiments. Furthermore, the number of branches, but not their chemical nature, was crucial for determining the cellular uptake mechanism of TPAs and their intracellular fate. The uptake of all TPAs is an active endocytic process but two- and three-branch compounds are taken up via distinct endocytosis pathways, clathrin-dependent or -independent (predominantly caveolae-dependent), respectively. Two-branch TPAs preferentially target mitochondria and photoinduce both apoptosis and a proper necrotic process, whereas three-branch TPAs preferentially target late endosomes and photoinduce apoptosis only.

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Année de publication : 2019

Mouawad L., Beswick V., Jamin N., Montigny C., Quiniou E., Barbot T. (2019 Dec 18)

Deciphering the mechanism of inhibition of SERCA1a by sarcolipin using molecular simulations

bioRxiv : DOI : 10.1101/2019.12.17.879825 En savoir plus
Résumé

SERCA1a is an ATPase calcium pump that transports Ca2+ from the cytoplasm to the sarco/endoplasmic reticulum lumen. Sarcolipin (SLN), a transmembrane peptide, regulates the activity of SERCA1a by decreasing its Ca2+ transport rate, but its mechanism of action is still not well understood. To decipher this mechanism, we have performed normal modes analysis in the all-atom model, with the SERCA1a-SLN complex or the isolated SERCA1a embedded in an explicit membrane. The comparison of the results allowed us to provide an explanation for the action of SLN that is in good agreement with experimental observations. In our analyses, the presence of SLN locally perturbs the TM6 transmembrane helix and as a consequence modifies the position of D800, one of the key metal-chelating residues. Additionally, it reduces the flexibility of the gating residues, V304 and E309 in TM4, at the entrance of the Ca2+ binding sites, which would decrease the affinity for Ca2+. Unexpectedly, SLN has also an effect on the ATP binding site more than 35 r A away, due to the straightening of TM5, a long helix considered as the spine of the protein. The straightening of TM5 modifies the structure of the P-N linker that sits above it, and which comprises the 351DKTG354 conserved motif, resulting in an increase of the distance between ATP and the phosphorylation site. As a consequence, the turn-over rate could be affected. All this gives SERCA1a the propensity to go toward a Ca2+-deprived E2-like state in the presence of SLN and toward a Ca2+ high-affinity E1-like state in the absence of SLN, although the SERCA1a-SLN complex was crystallized in an E1-like state. In addition to a general mechanism of inhibition of SERCA1a regulatory peptides, this study also provides an insight in the conformational transition between the E2 and E1 states.

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Abegão L.M.G., Fonseca R.D., Santos F.A., Rodrigues J.J., Kamada K., Mendonça C.R., Piguel S., De Boni L. (2019 Aug 23)

First molecular electronic hyperpolarizability of series of π-conjugated oxazole dyes in solution: an experimental and theoretical study

RSC Adv. : 9 : 26476-26482 : DOI : 10.1039/C9RA05246A En savoir plus
Résumé

In this work, we report the experimental and theoretical first molecular electronic hyperpolarizability (βHRS) of eleven π-conjugated oxazoles compounds in toluene medium. The Hyper-Rayleigh Scattering (HRS) technique allowed the determination of the experimental dynamic βHRS values, by exciting the compounds with a picosecond pulse trains from a Q-switched and mode-locked Nd:YAG laser tuned at 1064 nm. Theoretical predictions based on time-dependent density functional theory level using the Gaussian 09 program package were performed with three different functionals (B3LYP, CAM-B3LYP, and M06-2X), to calculate both static and dynamic theoretical βHRS values. Good accordance was found between the experimental and theoretical values, in particular for the CAM-B3LYP and M06-2X functionals.

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El Hassen Mokrani, Abderrahmane Bensegueni, Ludovic Chaput, Claire Beauvineau, Hanane Djeghim, Liliane Mouawad (2019 May 1)

Identification of New Potent Acetylcholinesterase Inhibitors Using Virtual Screening and In Vitro Approaches.

Molecular informatics : 38 : 1800118 : DOI : 10.1002/minf.201800118 En savoir plus
Résumé

Acetylcholinesterase (AChE) is currently the most favorable target for the symptomatic treatment and reduction of Alzheimer’s disease (AD). In order to identify new potent inhibitors of this enzyme, we describe herein a new structure‐based virtual screening (SBVS) using the Institut Curie‐CNRS chemical library (ICCL), which contained at the screening date 14307 compounds. The strategy undertaken in this work consisted of the use of several docking programs in SBVS calculations followed by the application of a consensus method (vSDC) and a scrupulous visual analysis. It allowed us to obtain a high degree of success, with a yield of almost 86 %, since 12 hits were identified among only 14 molecules tested in vitro. Still more remarkably, 6 of these hits were more active than galantamine, the reference inhibitor. These hits were predicted to have good ADMET properties. The two most promising compounds can serve as leads for AD treatment.

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Morgan Pellerano, Delphine Naud-Martin, Florence Mahuteau-Betzer, Marie Morille, May Catherine Morris (2019 Feb 15)

Fluorescent biosensor for detection of the R248Q aggregation-prone mutant of p53.

Chembiochem : a European journal of chemical biology : 20 : 605-613 : DOI : 10.1002/cbic.201800531 En savoir plus
Résumé

The p53 tumour suppressor and guardian of the genome undergoes missense mutations which lead to functional inactivation in 50% human cancers. These mutations occur mostly in the DNA-binding domain of the protein and several of these induce conformational changes which lead to amyloid-like protein aggregation. Here we describe a fluorescent biosensor that reports on the R248Q mutant of p53 in vitro and in living cells, engineered through conjugation of an environmentally-sensitive probe onto a peptide derived from the primary aggregation segment of p53.This biosensor was characterized both in vitro and by fluorescence microscopy following facilitated delivery into cultured cells. We show that this biosensor preferentially reports on the p53 R248Q mutant in PC9 lung cancer cell line compared to other lung cancer cell lines harbouring either wildtype or no p53.

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Pauline Gilson, Morgane Couvet, Laetitia Vanwonterghem, Maxime Henry, Julien Vollaire, Vladimir Baulin, Marco Werner, Anna Orlowska, Véronique Josserand, Florence Mahuteau-Betzer, Laurence Lafanechère, Jean-Luc Coll, Benoit Busser, Amandine Hurbin (2019 Feb 1)

The pyrrolopyrimidine colchicine-binding site agent PP-13 reduces the metastatic dissemination of invasive cancer cells in vitro and in vivo.

Biochemical pharmacology : 160 : 1-13 : DOI : S0006-2952(18)30503-3 En savoir plus
Résumé

Standard chemotherapies that interfere with microtubule dynamics are a chemotherapeutic option used for the patients with advanced malignancies that invariably relapse after targeted therapies. However, major efforts are needed to reduce their toxicity, optimize their efficacy, and reduce cancer chemoresistance to these agents. We previously identified a pyrrolo[2,3d]pyrimidine-based microtubule-depolymerizing agent (PP-13) that binds to the colchicine site of β-tubulin and exhibits anticancer properties in solid human cancer cells, including chemoresistant subtypes. Here, we investigated the therapeutic potential of PP-13 in vitro and in vivo. PP-13 induced a mitotic blockade and apoptosis in several cancer cells cultured in two-dimensions or three-dimensions spheroids, in conjunction with reduced cell proliferation. Capillary-like tube formation assays using HUVECs showed that PP-13 displayed antiangiogenic properties. It also inhibited cancer cell motility and invasion, in in vitro wound-healing and transwell migration assays. Low concentration PP-13 (130 nmol.L) treatment significantly reduced the metastatic invasiveness of human cancer cells engrafts on chicken chorioallantoic membrane. In nude mice, 0.5 or 1 mg.kg PP-13 intraperitoneally administered three-times a week reduced the sizes of paclitaxel-refractory orthotopic breast tumors, delayed the progression of metastasis, and decreased the global metastatic load compared to 0.5 mg.kg paclitaxel or vehicle alone. PP-13 did not show any apparent early adverse effect in vivo. These data suggest that PP-13 is a promising alternative to standard chemotherapy in antimitotic drug-refractory tumors, especially through its impact on metastasis.

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Delphine Naud-Martin, Corinne Landras-Guetta, Daniela Verga, Deepanjan Ghosh, Sylvain Achelle, Florence Mahuteau-Betzer, Sophie Bombard, Marie-Paule Teulade-Fichou (2019 Jan 26)

Selectivity of Terpyridine Platinum Anticancer Drugs for G-quadruplex DNA.

Molecules (Basel, Switzerland) : 24 : 404 : DOI : 10.3390/molecules24030404 En savoir plus
Résumé

Guanine-rich DNA can form four-stranded structures called G-quadruplexes (G4s) that can regulate many biological processes. Metal complexes have shown high affinity and selectivity toward the quadruplex structure. Here, we report the comparison of a panel of platinum (II) complexes for quadruplex DNA selective recognition by exploring the aromatic core around terpyridine derivatives. Their affinity and selectivity towards G4 structures of various topologies have been evaluated by FRET-melting (Fluorescence Resonance Energy Transfert-melting) and Fluorescent Intercalator Displacement (FID) assays, the latter performed by using three different fluorescent probes (Thiazole Orange (TO), TO-PRO-3, and PhenDV). Their ability to bind covalently to the c-myc G4 structure in vitro and their cytotoxicity potential in two ovarian cancerous cell lines were established. Our results show that the aromatic surface of the metallic ligands governs, in vitro, their affinity, their selectivity for the G4 over the duplex structures, and platination efficiency. However, the structural modifications do not allow significant discrimination among the different G4 topologies. Moreover, all compounds were tested on ovarian cancer cell lines and normal cell lines and were all able to overcome cisplatin resistance highlighting their interest as new anticancer drugs.

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M Schmidt-Cernohorska, I Zhernov, E Steib, M Le Guennec, R Achek, S Borgers, D Demurtas, L Mouawad, Z Lansky, V Hamel, P Guichard (2019 Jan 19)

Flagellar microtubule doublet assembly in vitro reveals a regulatory role of tubulin C-terminal tails.

Science (New York, N.Y.) : 363 : 285-288 : DOI : 10.1126/science.aav2567 En savoir plus
Résumé

Microtubule doublets (MTDs), consisting of an incomplete B-microtubule at the surface of a complete A-microtubule, provide a structural scaffold mediating intraflagellar transport and ciliary beating. Despite the fundamental role of MTDs, the molecular mechanism governing their formation is unknown. We used a cell-free assay to demonstrate a crucial inhibitory role of the carboxyl-terminal (C-terminal) tail of tubulin in MTD assembly. Removal of the C-terminal tail of an assembled A-microtubule allowed for the nucleation of a B-microtubule on its surface. C-terminal tails of only one A-microtubule protofilament inhibited this side-to-surface tubulin interaction, which would be overcome in vivo with binding protein partners. The dynamics of B-microtubule nucleation and its distinctive isotropic elongation was elucidated by using live imaging. Thus, inherent interaction properties of tubulin provide a structural basis driving flagellar MTD assembly.

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Année de publication : 2018

Tom Baladi, Jessy Aziz, Florent Dufour, Valentina Abet, Véronique Stoven, François Radvanyi, Florent Poyer, Ting-Di Wu, Jean-Luc Guerquin-Kern, Isabelle Bernard-Pierrot, Sergio Marco Garrido, Sandrine Piguel (2018 Nov 1)

Design, synthesis, biological evaluation and cellular imaging of imidazo[4,5-b]pyridine derivatives as potent and selective TAM inhibitors.

Bioorganic & medicinal chemistry : 26 : 5510-5530 : DOI : 10.1016/j.bmc.2018.09.031 En savoir plus
Résumé

The TAM kinase family arises as a new effective and attractive therapeutic target for cancer therapy, autoimmune and viral diseases. A series of 2,6-disubstituted imidazo[4,5-b]pyridines were designed, synthesized and identified as highly potent TAM inhibitors. Despite remarkable structural similarities within the TAM family, compounds 28 and 25 demonstrated high activity and selectivity in vitro against AXL and MER, with IC value of 0.77 nM and 9 nM respectively and a 120- to 900-fold selectivity. We also observed an unexpected nuclear localization for compound 10Bb, thanks to nanoSIMS technology, which could be correlated to the absence of cytotoxicity on three different cancer cell lines being sensitive to TAM inhibition.

design,synthesis

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Luis M.G. Abegão, Ruben D Fonseca, Tárcius N Ramos, Florence Mahuteau-Betzer, Sandrine PIGUEL, José J. Rodrigues Jr, Cleber R. Mendonca, Sylvio Canuto, Daniel Luis Silva, and Leonardo De Boni (2018 Apr 12)

Oxazole dyes with potential for photoluminescence bioprobes: A two-Photon absorption study

The Journal of Physical Chemistry C : 122 : 10526-10534 : DOI : 10.1021/acs.jpcc.8b01904 En savoir plus
Résumé

In this work, six π-conjugated oxazole compounds dissolved in dichloromethane (DCM) were characterized with linear and nonlinear optical measurements. Z-Scan with femtosecond laser pulses was employed to determine the two-photon absorption (TPA) spectra. Other photophysical parameters, such as: absorbance, solvatochromism, lifetime fluorescence and fluorescence anisotropy were evaluated with linear optical techniques. The experimental TPA cross-section spectra were adjusted by Sum-Over-States (SOS) model, in which important parameters such as transition dipole moments and broadening parameters were determined. In order to better understand the TPA spectra of the oxazole compounds, quantum-chemical calculations using the response function formalism and the DFT level of theory were performed. Using the results provided by the quantum-chemical calculations and the broadening parameters estimated through the application of the SOS model, the TPA spectra were simulated by the superposition (summation) of individual homogeneous Lorentzian absorption profiles.

jp-2018-01904m_0006

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Marius Mamone, Jessy Aziz, Julie Le Bescont, Sandrine Piguel (2018 Jan 18)

Aminocarbonylation of N-Containing Heterocycles with Aromatic Amines Using Mo(CO)6

Synthesis : 50 : 1521-1526 : DOI : 10.1055/s-0037-1609152 En savoir plus
Résumé

We describe herein the palladium-catalyzed aminocarbonylation of nitrogen-containing heterocycles with aniline derivatives using molybdenum hexacarbonyl as a CO solid source, expanding the scope of the limited examples. This method is compatible with a variety of substitutions on the aniline moiety. The simple reaction conditions include easily available Pd(dppf)Cl2 catalyst, DBU as base in DMF at 120 °C for 3 hours in sealed tube thereby leading to the isolation of 21 compounds with yields ranging from 18 to 82%. We also show that double aminocarbonylation reactions are possible in satisfactory yields regarding both coupling partners.

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Hammerer F., Poyer F., Fourmois L., Chen S., Garcia G., Teulade-Fichou M.P., Maillard P., Mahuteau-Betzer F. (2018 Jan 1)

Mitochondria-targeted cationic porphyrin-triphenylamine hybrids for enhanced two-photon photodynamic therapy

Bioorganic & Medicinal Chemistry : 26 : 107-118 : DOI : 10.1016/j.bmc.2017.11.024 En savoir plus
Résumé

The proof of concept for two-photon activated photodynamic therapy has already been achieved for cancer treatment but the efficiency of this approach still heavily relies on the availability of photosensitizers combining high two-photon absorption and biocompatibility. In this line we recently reported on a series of porphyrin-triphenylamine hybrids which exhibit high singlet oxygen production quantum yield as well as high two-photon absorption cross-sections but with a very poor cellular internalization. We present herein new photosensitizers of the same porphyrin-triphenylamine hybrid series but bearing cationic charges which led to strongly enhanced water solubility and thus cellular penetration. In addition the new compounds have been found localized in mitochondria that are preferential target organelles for photodynamic therapy. Altogether the strongly improved properties of the new series combined with their specific mitochondrial localization lead to a significantly enhanced two-photon activated photodynamic therapy efficiency.

Mitochondria-targeted cationic porphyrin-triphenylamine hybrids for enhanced two-photon photodynamic therapy

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Année de publication : 2017

Pauline Gilson, Fernando Josa-Prado, Claire Beauvineau, Delphine Naud-Martin, Laetitia Vanwonterghem, Florence Mahuteau-Betzer, Alexis Moreno, Pierre Falson, Laurence Lafanechère, Véronique Frachet, Jean-Luc Coll, Jose Fernando Díaz, Amandine Hurbin, Benoit Busser (2017 Sep 2)

Identification of pyrrolopyrimidine derivative PP-13 as a novel microtubule-destabilizing agent with promising anticancer properties.

Scientific reports : 7 : 10209 : DOI : 10.1038/s41598-017-09491-9 En savoir plus
Résumé

Despite the emergence of targeted therapies and immunotherapy, chemotherapy remains the gold-standard for the treatment of most patients with solid malignancies. Spindle poisons that interfere with microtubule dynamics are commonly used in chemotherapy drug combinations. However, their troublesome side effects and the emergence of chemoresistance highlight the need for identifying alternative agents. We performed a high throughput cell-based screening and selected a pyrrolopyrimidine molecule (named PP-13). In the present study, we evaluated its anticancer properties in vitro and in vivo. We showed that PP-13 exerted cytotoxic effects on various cancer cells, including those resistant to current targeted therapies and chemotherapies. PP-13 induced a transient mitotic blockade by interfering with both mitotic spindle organization and microtubule dynamics and finally led to mitotic slippage, aneuploidy and direct apoptotic death. PP-13 was identified as a microtubule-targeting agent that binds directly to the colchicine site in β-tubulin. Interestingly, PP-13 overcame the multidrug-resistant cancer cell phenotype and significantly reduced tumour growth and metastatic invasiveness without any noticeable toxicity for the chicken embryo in vivo. Overall, PP-13 appears to be a novel synthetic microtubule inhibitor with interesting anticancer properties and could be further investigated as a potent alternative for the management of malignancies including chemoresistant ones.

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Aziz Jessy, Piguel Sandrine (2017 Aug 25)

An update on direct C–H bond functionalization of nitrogen-containing fused heterocycles

Synthesis : 49 : 4562-4585 : DOI : 10.1055/s-0036-1590859 En savoir plus
Résumé

This report highlights the recent advances in direct C–H bond functionalization of 5,5- and 6,5-fused heterocycles containing at least two nitrogen atoms. Besides C–C bond formation, C–N, C–S, C–P, and C–Si bonds can also be created via a metal-catalyzed process. Some examples, where a C–H functionalization approach was applied for the synthesis of drug candidates, will be presented as well.

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Claire Beauvineau, Corinne Guetta, Marie-Paule Teulade-Fichou, Florence Mahuteau-Betzer (2017 Aug 14)

PhenDV, a turn-off fluorescent quadruplex DNA probe for improving the sensitivity of drug screening assays

Organic & Biomolecular Chemistry : 15 : 7117-7121 : DOI : 10.1039/c7ob01705g En savoir plus
Résumé

We report a new turn-off fluorescent probe, PhenDV, for the identification of high affinity quadruplex (G4) DNA ligands. This push–pull fluorophore displays a high fluorescence quantum yield in water (ΦF = 0.21) and is a selective and strong quadruplex DNA binder. We describe its use as a fluorescent indicator for the G4 Fluorescent Intercalator Displacement (FID) assay as its fluorescence is strongly quenched when bound to G4 DNA and fully restored when displaced by ligand. This probe improves the sensitivity of the G4-FID assay, as the read out relies on increased fluorescence instead of quenching observed with classical on/off probes

PhenDV-Mahuteau-Betzer

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