Sunday, June 6

5:00-6:00 p.m Early Registration, Poster and Exhibit Setup

Monday, June 7

8:00 Registration, Morning Coffee, Poster and Exhibit Setup

GPCR Science:
Characterization and Function

9:00 Welcome by Session Chairperson
Dr. Annette Gilchrist, Northwestern University

9:15 Determining Global and Class-Specific Functions
Mr. Srinivasan Madabushi, Graduate Student, Lichtarge Lab, Molecular and Human Genetics, Baylor College of Medicine
Using Evolutionary Trace(ET) we identified a canonical signal transduction mechanism where ligand binding induces conformational changes propagated through adjacent trigger, linking core and coupling regions relevant across many class A families as well as opsin family specific residues that correctly identify the retinal binding pocket. Correlation with existing mutational data in literature & databases supports our conclusions and identifies few novel candidates. We mutated two novel predictions:L79 & W175 in bovine rhodopsin that resulted in constitutive activity and rhodopsin regeneration defects supporting the ability of ET to identify functional determinants in GPCRs. (JBC In Press article) Co-Author: Olivier Lichtarge, Baylor College of Medicine

9:45 Flow Cytometric Analysis of GPCR Assemblies and Their Applications in Drug Discovery
Dr. Larry A Sklar, Professor of Pathology, University of New Mexico School of Medicine
We have developed several new discovery approaches for G protein coupled receptors. One uses a homogeneous, small volume bead-based approach for soluble GPCR molecular assemblies (ternary complex of ligand, receptor, and G protein heterotrimer). We applied it to several classical problems including the steps in activation of ternary complex, and a rigorous analysis of assemblies involving full and partial agonists. We have also used an integrative process of virtual screening and high throughput flow cytometry (HyperCyt) with targeted libraries to discover new classes of small molecules for peptide binding receptors. Co-Authors: Peter Simons, Anna Waller, Sean Biggs, Daniel Cimino, Terry Foutz, Tione Buranda, Bruce Edwards, Susan Young, Tudor Oprea, Cristian Bologa, and Eric Prossnitz

10:15 Characterization of Orphan GPCRs as Targets for Drug Discovery
Dr. Michel Detheux, Head of Target Discovery, Euroscreen
The recent deorphanization of several GPCRs required complex approaches. The different pitfalls will be discussed with review of the various strategies to overcome the limitations encountered with orphan GPCRs. Original approaches including screening of functional antibodies will be described. The identification of chemerin receptor will illustrate the use of a recently deorphanized GPCR for drug discovery
10:45 Poster and Exhibit Viewing Coffee Break

11:15 Ligand-Selective GPCR Conformations and Signaling
Dr. Arthur Christopoulos, Department of Pharmacology, University of Melbourne
Classic pharmacological approaches to GPCR-based drug discovery have been driven by the assumption that a single active GPCR state controls drug efficacy, and that differences between drugs tested against a GPCR target are due to differences in the quantity of that active state engendered by each drug. More recent experimental findings, however, illustrate that the quality of drug efficacy is also an important property that cannot be overlooked in the drug discovery process. Such findings suggest that many GPCR drug candidates induce multiple, ligand-specific, conformations that manifest cell-dependent "phenotypic" behaviors; this can lead to a dissimilitude between findings made in recombinant systems used to discover drugs, and effects in the target systems for which they are intended. This presentation will illustrate some these concepts with examples of ligand-directed "stimulus trafficking" involving GPCRs interacting with classic (orthosteric) ligands, allosteric modulators and/or accessory cellular proteins.

11:45 Identification of Natural and Surrogate Ligands for Orphan GPCRs and Beyond
Dr. Jie Zhang, Principle Scientist, Aventis Pharmaceuticals
The Aventis GPCR Chemical Biology platform has focused on rationally improving the deorphaning process. The resulting strategy facilitates target selection based on informatic analysis as well as disease hypothesis generation through expression profiling. GPCR assays were analyzed and selected to suit the deorphaning needs and focused libraries have been developed for targeting specific receptor subfamilies. The presentation details the identification of both natural as well surrogate ligands. In addition, these ligands were utilized to further our understanding of the biological function of their receptors.

12:15 Panel Discussion with all Morning Speakers

12:30 Luncheon

Assays and Screening

1:50 Comments by Session Chairperson
Dr. Miguel Garcia-Guzman, Group Leader, Discovery Biology, Vertex Pharmaceuticals

2:00 Identification of Peptide Ligands for GPCR using a Functional Assay
Dr. Yinghe Hu, Shanghai Institute of Brain Functional Genomics, East China Normal University
We have developed a universal functional assay for G-protein coupled receptors (GPCRs) using a reporter gene assay. The assay was successfully used to test the activity of more than twenty different GPCRs. In addition, alpha-melanocyte stimulating hormone (alpha-MSH) was generated In Vitro. The biological activity of the peptide was examined in a cell line expressing human melanocortin 4 receptor (MC4R). We propose that it should be possible to identify novel bioactive peptides for orphan GPCRs by the combination of In Vitro processing and the GPCR functional assay.

2:30 High-Throughput Screening Approaches to Identifying Subtype Selective GPCR Agonists: Applications for Muscarinic Receptors
Dr. Miguel Garcia-Guzman
I propose to describe the combination of functional cell-based assays with our unique high-throughput screening approaches to identify selective ligands for different subtypes of muscarinic receptors. This is family with large therapeutic opportunities that require high levels of compound selectivity for successful drug-discovery and development.

3:00 G Protein Dependent Versus Arrestin Dependent Signaling: Pros and Cons of Current "Universal" Cell Based Assays and Implications for Ligand Pharmacology
Dr. Evi Kostenis, Head of In Vitro Pharmacology, 7TM Pharma A/S and University of Copenhagen
Identification of endogenous or surrogate modulators of 7 transmembrane G protein coupled receptors (7TM GPCRs) requires technologies that allow ligand occupancy of the receptors to be converted into robust functional assay signals. Of particular interest are universal screening systems such that activation of any GPCR can be detected with a common assay end point. Currently, universal assay systems are either based on the use of promiscuous/chimeric G proteins or the translocation of b-arrestin from the cytosol to the plasma membrane upon receptor activation. Recent literature indicates that drugs known as antagonists/inverse agonists for classical G protein-mediated second messenger pathways can simultaneously act as agonists in G protein-independent, arrestin-dependent signalling events. These findings add an additional layer of complexity to the drug discovery process and impose the need to revisit current assays for characterization of ligand pharmacology as well as to establish assays that allow to measure activation of G protein-independent signalling by G protein coupled seven transmembrane receptors.

3:30 Poster and Exhibit Viewing, Refreshment Break

4:00 High Speed Single Cell, Multiplexed Lead Discovery Pharmacology
Dr. John T. Ransom, Senior Director, Biology, Novasite Pharmaceuticals
Single cell analysis by Flow Cytometry (FCM) provides very high statistical confidence within a brief analysis time, and we have developed an automated sampling system that delivers mixtures of individual compounds and cells to the FCM. The system detects weak ligands, unveiling novel chemical scaffolds otherwise unappreciated, and permits appreciation of a spectrum of activities from full agonist through weak partial agonist to antagonist. When combined with technology to individually label up to 20 different receptor populations that can be analyzed in parallel, we have found that well known serotonergic and dopaminergic compounds are poorly selective and exhibit both weak partial agonist and antagonist properties. Information derived with this technique, with other Novasite technologies, provides 10 fold more hits and rapidly guides us towards development of more selective compounds for improved therapeutic utility.

4:30 Cell-based GPCR Screening Assays using Enzyme Fragment Complementation
Dr. Richard Eglen, CSO, DiscoveRx Corp.
The talk will cover new applications of DiscoveRx's technology to measure receptor activation, trafficking and second messenger mobilization (cAMP, IP3). The talk will include data from both DiscoveRx and several pharmaceutical companies using the technology in cell based screens of GPCRs.

5:00 A Cell-Based Drug Screening Strategy for G-Protein Coupled Receptors
Dr. Brian O’Dowd, Professor, Pharmacology, University of Toronto
We have developed the Multipurpose Original Cellular Assay (MOCA), for the identification of compounds interacting with G protein coupled receptors (GPCRs). MOCA involves the robust translocation of a GPCR with a small genetic modification, a nuclear localization sequence (NLS), from the cell surface in a basal time-dependent and ligand independent manner with no recycling back to the cell surface. Interaction of a GPCR with compounds prevents the translocation from the cell surface and is measured as receptor retained on the cell surface. This assay is suitable for the identification of chemicals interacting with or modifying the activity of both known and orphan GPCRs. MOCA can also enable the evaluation of the ability of GPCRs to oligomerize generating novel heteromeric drug targets. The method does not depend on any prior knowledge of G protein or second messenger coupling. The method is adaptable for instrumentation used in receptor detection, such as the fluorometer, confocal microscope, scintillation counter and FACS.

5:30 End of Day One

Call for Sponsors and Exhibitors 
Showcase your company's expertise, brand your solutions and develop revenue opportunities with qualified decision-makers by becoming an exhibitor or sponsor at GPCRs and Kinases. Sponsorship opportunities include: technology workshop presentations, poster competitions, refreshment breaks and networking receptions just to name a few. We also have high-visibility items such as conference padfolios and badge lanyards, which will brand your company name and logo.

For more information on exhibiting and sponsoring, please contact Arnie Wolfson at 781-972-5431, or awolfson@healthtech.com