Michel Bouvier
Université de Montréal, Biochemistry (Biochemie), Faculty Member
- Professor of Biochemistry and Molecular Medicine, General Director of Institut for Research in Immunology and Cancer,... moreProfessor of Biochemistry and Molecular Medicine, General Director of Institut for Research in Immunology and Cancer, Canada Research (IRIC) Chair in Signal Transduction and Molecular Pharmacology.edit
Research Interests:
Research Interests: Chemistry, Biology, Cell Biology, Biological Chemistry, Medicine, and 15 moreSignal Transduction, Biological Sciences, Internalization, Humans, Endocytosis, CHEMICAL SCIENCES, Hydrazones, Amino Acid Sequence, Lysosomes, Protein Binding, Molecular Sequence Data, Cell Membrane, proteolysis, Protein Kinase C, and Medical and Health Sciences
G protein-coupled receptors are important drug targets that engage and activate signaling transducers in multiple cellular compartments. Delineating therapeutic signaling from signaling associated with adverse events is an important step... more
G protein-coupled receptors are important drug targets that engage and activate signaling transducers in multiple cellular compartments. Delineating therapeutic signaling from signaling associated with adverse events is an important step towards rational drug design. The glucagon-like peptide-1 receptor (GLP-1R) is a validated target for the treatment of diabetes and obesity, but drugs that target this receptor are a frequent cause of adverse events. Using recently developed biosensors, we explored the ability of GLP-1R to activate 15 pathways in 4 cellular compartments and demonstrate that modifications aimed at improving the therapeutic potential of GLP-1R agonists greatly influence compound efficacy, potency, and safety in a pathway- and compartment-selective manner. These findings, together with comparative structure analysis, time-lapse microscopy, and phosphoproteomics, reveal unique signaling signatures for GLP-1R agonists at the level of receptor conformation, functional sel...
Research Interests:
G protein-coupled receptors (GPCRs) translate binding of extracellular ligands into intracellular responses through conformational changes. Ligand properties are described by the maximum response (efficacy) and the agonist concentration... more
G protein-coupled receptors (GPCRs) translate binding of extracellular ligands into intracellular responses through conformational changes. Ligand properties are described by the maximum response (efficacy) and the agonist concentration at half-maximal response (potency). Integrating structural changes with pharmacological properties remains challenging and has not yet been performed at the resolution of individual amino acids. We use epinephrine and β2-adrenergic receptor as a model to integrate residue-level pharmacology data with intramolecular residue contact data describing receptor activation. This unveils the allosteric networks driving ligand efficacy and potency. We provide detailed insights into how structural rearrangements are linked to fundamental pharmacological properties at single-residue level in a receptor-ligand system. Our approach can be used to determine such pharmacological networks for any receptor-ligand complex.
Research Interests:
Research Interests:
Research Interests:
Research Interests: Chemistry, Biology, Cell Biology, Biological Chemistry, Medicine, and 15 moreSignal Transduction, Biological Sciences, Internalization, Humans, Endocytosis, CHEMICAL SCIENCES, Hydrazones, Amino Acid Sequence, Lysosomes, Protein Binding, Molecular Sequence Data, Cell Membrane, proteolysis, Protein Kinase C, and Medical and Health Sciences
Research Interests:
Research Interests:
Research Interests:
Research Interests: Chemistry, Biology, Cell Biology, Biological Chemistry, Medicine, and 15 moreSignal Transduction, Biological Sciences, Internalization, Humans, Endocytosis, CHEMICAL SCIENCES, Hydrazones, Amino Acid Sequence, Lysosomes, Protein Binding, Molecular Sequence Data, Cell Membrane, proteolysis, Protein Kinase C, and Medical and Health Sciences
Research Interests:
ABSTRACT One of the most fascinating features of β-adrenergic receptors (βARs) signaling systems is their high degree of plasticity. This permits the cell to adapt to its environment and may play a major role in the sorting and... more
ABSTRACT One of the most fascinating features of β-adrenergic receptors (βARs) signaling systems is their high degree of plasticity. This permits the cell to adapt to its environment and may play a major role in the sorting and integration of the information detected at the receptor levels. βARs, which belong to the family of G-protein-coupled receptors, are the target of various regulatory processes. In particular, negative regulation and desensitization in response to sustained activation have been well researched. Changes in the responsiveness of βARs are believed to contribute to the phenomenon of habituation and withdrawal syndrome associated with the use of β-adrenergic agonists and antagonists, respectively. Because βARs represent important pharmacological targets in the treatment of hypertension, angina pectoris, arrhythmias, heart failure, and obesity, analysis of the mechanisms leading to alterations of βAR responsiveness is essential, because it may lead to the identification of new means to normalize the receptor function. Recent evidence suggests subtype-specific signaling between β1AR and β2AR. Indeed, although convincing data show that, as β1AR, β2AR can promote positive chronotropic and inotropic responses in human ventricle, discrepancies between the efficacy of β2AR to stimulate adenylyl cyclase and to modulate contractile function have raised questions regarding the precise relation between cyclic adenosine monophosphate (cAMP) production and cardiac regulation.
Research Interests:
ABSTRACT
Research Interests:
Communication across membranes controls critical cellular processes and is achieved by receptors translating extracellular signals into selective cytoplasmic responses. While receptor tertiary structures can now be readily characterized,... more
Communication across membranes controls critical cellular processes and is achieved by receptors translating extracellular signals into selective cytoplasmic responses. While receptor tertiary structures can now be readily characterized, receptor associations into quaternary structures are very challenging to study and their implications in signal transduction remain poorly understood. Here, we report a computational approach for predicting membrane receptor self-associations, and designing receptor oligomers with various quaternary structures and signaling properties. Using this approach, we designed chemokine receptor CXCR4 dimers with reprogrammed stabilities, conformations, and abilities to activate distinct intracellular signaling proteins. In agreement with our predictions, the designed CXCR4s dimerized through distinct conformations and displayed different quaternary structural changes upon activation. Consistent with the active state models, all engineered CXCR4 oligomers ac...
Research Interests:
Research Interests:
Research Interests:
Two-thirds of human hormones and one-third of clinical drugs act on membrane receptors that couple to G proteins to achieve appropriate functional responses. While G protein transducers from literature are annotated in the Guide to... more
Two-thirds of human hormones and one-third of clinical drugs act on membrane receptors that couple to G proteins to achieve appropriate functional responses. While G protein transducers from literature are annotated in the Guide to Pharmacology database, two recent large-scale datasets now expand the receptor-G protein ‘couplome’. However, these three datasets differ in scope and reported G protein couplings giving different coverage and conclusions on GPCR-G protein signaling. Here, we report a common coupling map uncovering novel couplings supported by both large-scale studies, the selectivity/promiscuity of GPCRs and G proteins, and how the co-coupling and co-expression of G proteins compare to the families from phylogenetic relationships. The coupling map and insights on GPCR-G protein selectivity will catalyze advances in receptor research and cellular signaling towards the exploitation of G protein signaling bias in design of safer drugs.
Research Interests:
Activation of the G protein-coupled receptors by agonists may result in the activation of one or more G proteins, and in the recruitment of arrestins. The balance of activation of different pathways can be influenced by the ligand. Using... more
Activation of the G protein-coupled receptors by agonists may result in the activation of one or more G proteins, and in the recruitment of arrestins. The balance of activation of different pathways can be influenced by the ligand. Using BRET-based biosensors, we showed that the vasopressin V2 receptor activates or at least engages many different G proteins across all G protein subfamilies in response to its native agonist arginine vasopressin (AVP). This includes members of the Gi/o and G12/13 families that have not been previously reported. These signalling pathways are also activated by the synthetic peptide desmopressin and natural homologs of AVP, namely oxytocin and the non-mammalian hormone vasotocin. They demonstrated varying degrees of functional selectivity relative to AVP, as quantified using the operational model for quantifying ligand bias. Additionally, we modelled G protein activation as a Michaelis-Menten reaction. This approach provided a complementary way to quanti...
Research Interests:
ABSTRACTMalaria causes millions of deaths worldwide and is considered a huge public health problem for underdeveloped countries. The most severe cases of malaria present complications of the host circulatory system, which may cause... more
ABSTRACTMalaria causes millions of deaths worldwide and is considered a huge public health problem for underdeveloped countries. The most severe cases of malaria present complications of the host circulatory system, which may cause clogging and rupture of blood vessels, leading to death or important sequelae. Because of the previously suggested role of thrombin and platelet aggregation in Plasmodium falciparum biology, we hypothesized that one of the GPCR-like proteins identified in the genome of the parasite, P. falciparum serpentine receptor 12 (PfSR12), could be a thrombin-activated GPCR. To test this hypothesis we used a series of Bioluminescence and Bioluminescence Resonance Energy Transfer (BRET)-based biosensors to investigate the signaling activity of PfSR12. Using an Obelin based biosensor, thrombin promoted a PfSR12-dependent cytosolic Ca2+ rise in HEK293 cells. This Ca2+ mobilization was accompanied by DAG formation and PKC activation as detected using DAG and PKC BRET-ba...
Research Interests:
Signaling diversity of G protein-coupled (GPCR) ligands provides novel opportunities to develop more effective, better-tolerated therapeutics. Taking advantage of these opportunities requires identifying which effectors should be... more
Signaling diversity of G protein-coupled (GPCR) ligands provides novel opportunities to develop more effective, better-tolerated therapeutics. Taking advantage of these opportunities requires identifying which effectors should be specifically activated or avoided so as to promote desired clinical responses and avoid side effects. However, identifying signaling profiles that support desired clinical outcomes remains challenging. This study describes signaling diversity of mu opioid receptor (MOR) ligands in terms of logistic and operational parameters for ten different in vitro readouts. It then uses unsupervised clustering of curve parameters to: classify MOR ligands according to similarities in type and magnitude of response, associate resulting ligand categories with frequency of undesired events reported to the pharmacovigilance program of the Food and Drug Administration and associate signals to side effects. The ability of the classification method to associate specific in vitr...
Research Interests: Neuroscience, Computational Biology, Clustering and Classification Methods, Neuropharmacology, Clinical Pharmacology, and 15 moreClustering Algorithms, Clinical Biochemistry, Cell Signaling, Medicine, Multidisciplinary, Cellular Signaling, GPCRs, Clustering, Cluster Analysis, GPCR, Morphine, Clinical Sciences, Cluster, Nature Communications, and G Protein Coupled Receptors
Research Interests: Electron Microscopy, Biology, Transmission Electron Microscopy, Confocal Microscopy, Medicine, and 11 moreSignal Transduction, Biological Sciences, Humans, G protein-coupled receptors, cyclic AMP, Cell, Endosomes, Beta-Arrestins, heterotrimeric G-protein, G Protein Coupled Receptors, and Medical and Health Sciences
ABSTRACT
Research Interests:
Research Interests:
Research Interests:
Research Interests: Biology, Macrophages, Molecular Genetics, Medicine, Cell line, and 14 moreHumans, Cholesterol, apolipoprotein A-I, Clinical Sciences, Monocytes, Time Factors, Human Fibroblasts, Lipoprotein a, Gene Expression Regulation, Down-Regulation, Immunoblotting, reverse cholesterol transport, fibroblasts, and Human skin
Research Interests: Endocrinology, Biology, Medicine, Humans, Internal Medicine, and 14 moreMutation, Female, Male, Hypoglycemia, Infant, Clinical Sciences, Melanocortin receptor, Exome Sequencing, Adrenocorticotropic Hormone, Alpha MSH, Glucocorticoids, Child preschool, ACTH receptor, and Paediatrics and reproductive medicine
Research Interests:
Research Interests:
In addition to G protein-coupled receptor (GPCR) desensitization and endocytosis, β-arrestin recruitment to ligand-stimulated GPCRs promotes non-canonical signalling cascades. Distinguishing the respective contributions of β-arrestin... more
In addition to G protein-coupled receptor (GPCR) desensitization and endocytosis, β-arrestin recruitment to ligand-stimulated GPCRs promotes non-canonical signalling cascades. Distinguishing the respective contributions of β-arrestin recruitment to the receptor and β-arrestin-promoted endocytosis in propagating receptor signalling has been limited by the lack of selective analytical tools. Here, using a combination of virtual screening and cell-based assays, we have identified a small molecule that selectively inhibits the interaction between β-arrestin and the β2-adaptin subunit of the clathrin adaptor protein AP2 without interfering with the formation of receptor/β-arrestin complexes. This selective β-arrestin/β2-adaptin inhibitor (Barbadin) blocks agonist-promoted endocytosis of the prototypical β2-adrenergic (β2AR), V2-vasopressin (V2R) and angiotensin-II type-1 (AT1R) receptors, but does not affect β-arrestin-independent (transferrin) or AP2-independent (endothelin-A) receptor ...
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Moulay D. Rochdi, Gabriel A. Vargas, Eric Carpentier, Geneviève Oligny-Longpré, Stanford Chen, Abraham Kovoor, Stephen E. Gitelman, Stephen M. Rosenthal, Mark von Zastrow and Michel Bouvier* Institut de Recherche en Immunologie et... more
Moulay D. Rochdi, Gabriel A. Vargas, Eric Carpentier, Geneviève Oligny-Longpré, Stanford Chen, Abraham Kovoor, Stephen E. Gitelman, Stephen M. Rosenthal, Mark von Zastrow and Michel Bouvier* Institut de Recherche en Immunologie et Cancérologie, Département de Biochimie and Groupe de Recherche Universitaire sur le Médicament, Université de Montréal, Montréal, Québec, H3C 3J7, Canada (M.D.R., E.C., G.O.-L., M.B.); Department of Psychiatry (G.A.V., S.C., A.K., M.vZ), Department Cellular & Molecular Pharmacology (M.vZ), and Department of Pediatrics, Division of Endocrinology (S.E.G., S.M.R.), UCSF, San Francisco, CA, USA Molecular Pharmacology Fast Forward. Published on February 16, 2010 as doi:10.1124/mol.109.061804
Cannabinoid CB1 and CB2 receptors are members of the G protein-coupled receptor family, which is the largest class of membrane proteins in the human genome. As part of the endocannabinoid system, they have many regulatory functions in the... more
Cannabinoid CB1 and CB2 receptors are members of the G protein-coupled receptor family, which is the largest class of membrane proteins in the human genome. As part of the endocannabinoid system, they have many regulatory functions in the human body. Their malfunction therefore triggers a diverse set of undesired conditions, such as pain, neuropathy, nephropathy, pruritus, osteoporosis, cachexia and Alzheimer’s disease. Although drugs targeting the system exist, the molecular and functional mechanisms involved are still poorly understood, preventing the development of better therapeutics with fewer undesired effects. One path toward the development of better and safer medicines targeting cannabinoid receptors relies on the ability of some compounds to activate a subset of pathways engaged by the receptor while sparing or even inhibiting the others, a phenomenon known as biased signaling. To take advantage of this phenomenon for drug development, a better profiling of the pathways en...
SUMMARYEzrin, Radixin and Moesin compose the family of ERM proteins. They link actin and microtubule filaments to the plasma membrane to control signaling and cell morphogenesis. Importantly, their activity promotes invasive properties of... more
SUMMARYEzrin, Radixin and Moesin compose the family of ERM proteins. They link actin and microtubule filaments to the plasma membrane to control signaling and cell morphogenesis. Importantly, their activity promotes invasive properties of metastatic cells from different cancer origins. Therefore, a precise understanding of how these proteins are regulated is important for the understanding of the mechanism controlling cell shape as well as providing new opportunities for the development of innovative cancer therapies. ERMs are believed to exist in two main conformational states: a close-inactive conformation in the cytoplasm that is recruited at the plasma membrane to convert into an open-active conformation. Here, we developed and characterized novel BRET-based conformational biosensors, compatible with high throughput screening, that monitor Ezrin, Radixin or Moesin individual activation in living cells. We showed that these biosensors faithfully monitor ERM activation and can be ...
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Biased signaling has been suggested as a means of selectively modulating a limited fraction of the signaling pathways for G-protein–coupled receptor family members. Hence, biased ligands may allow modulation of only the desired... more
Biased signaling has been suggested as a means of selectively modulating a limited fraction of the signaling pathways for G-protein–coupled receptor family members. Hence, biased ligands may allow modulation of only the desired physiological functions and not elicit undesired effects associated with pharmacological treatments. The ghrelin receptor is a highly sought antiobesity target, since the gut hormone ghrelin in humans has been shown to increase both food intake and fat accumulation. However, it also modulates mood, behavior, growth hormone secretion, and gastric motility. Thus, blocking all pathways of this receptor may give rise to potential side effects. In the present study, we describe a highly promiscuous signaling capacity for the ghrelin receptor. We tested selected ligands for their ability to regulate the various pathways engaged by the receptor. Among those, a biased ligand, YIL781, was found to activate the Gαq/11 and Gα12 pathways selectively without affecting the...
Research Interests:
Functional selectivity of G-protein-coupled receptors is believed to originate from ligand-specific conformations that activate only subsets of signaling effectors. In this study, to identify molecular motifs playing important roles in... more
Functional selectivity of G-protein-coupled receptors is believed to originate from ligand-specific conformations that activate only subsets of signaling effectors. In this study, to identify molecular motifs playing important roles in transducing ligand binding into distinct signaling responses, we combined in silico evolutionary lineage analysis and structure-guided site-directed mutagenesis with large-scale functional signaling characterization and non-negative matrix factorization clustering of signaling profiles. Clustering based on the signaling profiles of 28 variants of the β-adrenergic receptor reveals three clearly distinct phenotypical clusters, showing selective impairments of either the Gi or βarrestin/endocytosis pathways with no effect on Gs activation. Robustness of the results is confirmed using simulation-based error propagation. The structural changes resulting from functionally biasing mutations centered around the DRY, NPxxY, and PIF motifs, selectively linking ...
Research Interests:
Research Interests:
Substitution of arginine-137 of the vasopressin type 2 receptor (V2R) for histidine (R137H-V2R) leads to nephrogenic diabetes insipidus (NDI), whereas substitution of the same residue to cys-teine or leucine (R137C/L-V2R) causes the... more
Substitution of arginine-137 of the vasopressin type 2 receptor (V2R) for histidine (R137H-V2R) leads to nephrogenic diabetes insipidus (NDI), whereas substitution of the same residue to cys-teine or leucine (R137C/L-V2R) causes the nephrogenic syndrome of inappropriate antidiuresis (NSIAD). These two diseases have opposite clinical outcomes. Still, the three mutant receptors were shown to share constitutive -arrestin recruitment and endocyto-sis, resistance to vasopressin-stimulated cAMP production and mitogen-activated protein kinase activation, and compromised cell surface targeting, raising questions about the contribution of these phenomenons to the diseases and their potential treat-ments. Blocking endocytosis exacerbated the elevated basal cAMP levels promoted by R137C/L-V2R but not the cAMP pro-duction elicited by R137H-V2R, demonstrating that substitution of