title: Tyrosine Kinase 2-mediated Signal Transduction in T Lymphocytes Is Blocked by Pharmacological Stabilization of Its Pseudokinase Domain.
abstract: Inhibition of signal transduction downstream of the IL-23 receptor represents an intriguing approach to the treatment of autoimmunity. Using a chemogenomics approach marrying kinome-wide inhibitory profiles of a compound library with the cellular activity against an IL-23-stimulated transcriptional response in T lymphocytes, a class of inhibitors was identified that bind to and stabilize the pseudokinase domain of the Janus kinase tyrosine kinase 2 (Tyk2), resulting in blockade of receptor-mediated activation of the adjacent catalytic domain. These Tyk2 pseudokinase domain stabilizers were also shown to inhibit Tyk2-dependent signaling through the Type I interferon receptor but not Tyk2-independent signaling and transcriptional cellular assays, including stimulation through the receptors for IL-2 (JAK1- and JAK3-dependent) and thrombopoietin (JAK2-dependent), demonstrating the high functional selectivity of this approach. A crystal structure of the pseudokinase domain liganded with a representative example showed the compound bound to a site analogous to the ATP-binding site in catalytic kinases with features consistent with high ligand selectivity. The results support a model where the pseudokinase domain regulates activation of the catalytic domain by forming receptor-regulated inhibitory interactions. Tyk2 pseudokinase stabilizers, therefore, represent a novel approach to the design of potent and selective agents for the treatment of autoimmunity.
authors.affiliation: From the Departments of Molecular Structure and Design.
authors.forename: John S
authors.initials: JS
authors.lastname: Tokarski
authors.affiliation: Immunosciences Biology.
authors.forename: Adriana
authors.initials: A
authors.lastname: Zupa-Fernandez
authors.affiliation: Protein Science.
authors.forename: Jeffrey A
authors.initials: JA
authors.lastname: Tredup
authors.affiliation: the Department of Leads Discovery and Optimization, Bristol-Myers Squibb Research and Development, Wallingford, Connecticut 06492.
authors.forename: Kristen
authors.initials: K
authors.lastname: Pike
authors.affiliation: From the Departments of Molecular Structure and Design.
authors.forename: ChiehYing
authors.initials: C
authors.lastname: Chang
authors.affiliation: Protein Science.
authors.forename: Dianlin
authors.initials: D
authors.lastname: Xie
authors.affiliation: Immunosciences Biology.
authors.forename: Lihong
authors.initials: L
authors.lastname: Cheng
authors.affiliation: Leads Discovery and Optimization, and.
authors.forename: Donna
authors.initials: D
authors.lastname: Pedicord
authors.affiliation: From the Departments of Molecular Structure and Design.
authors.forename: Jodi
authors.initials: J
authors.lastname: Muckelbauer
authors.affiliation: From the Departments of Molecular Structure and Design.
authors.forename: Stephen R
authors.initials: SR
authors.lastname: Johnson
authors.affiliation: Protein Science.
authors.forename: Sophie
authors.initials: S
authors.lastname: Wu
authors.affiliation: Protein Science.
authors.forename: Suzanne C
authors.initials: SC
authors.lastname: Edavettal
authors.affiliation: Discovery Chemistry, Bristol-Myers Squibb Research and Development, Princeton, New Jersey 08543 and.
authors.forename: Yang
authors.initials: Y
authors.lastname: Hong
authors.affiliation: Protein Science.
authors.forename: Mark R
authors.initials: MR
authors.lastname: Witmer
authors.affiliation: the Department of Leads Discovery and Optimization, Bristol-Myers Squibb Research and Development, Wallingford, Connecticut 06492.
authors.forename: Lisa L
authors.initials: LL
authors.lastname: Elkin
authors.affiliation: Leads Discovery and Optimization, and.
authors.forename: Yuval
authors.initials: Y
authors.lastname: Blat
authors.affiliation: Discovery Chemistry, Bristol-Myers Squibb Research and Development, Princeton, New Jersey 08543 and.
authors.forename: William J
authors.initials: WJ
authors.lastname: Pitts
authors.affiliation: Discovery Chemistry, Bristol-Myers Squibb Research and Development, Princeton, New Jersey 08543 and.
authors.forename: David S
authors.initials: DS
authors.lastname: Weinstein
authors.affiliation: Immunosciences Biology, james.burke@bms.com.
authors.forename: James R
authors.initials: JR
authors.lastname: Burke
mesh_terms: D018360:Crystallography, X-Ray; D004795:Enzyme Stability; D006801:Humans; D053613:Janus Kinase 1 / Q000235:genetics / Q000378:metabolism; D053616:Janus Kinase 3 / Q000235:genetics / Q000378:metabolism; D008958:Models, Molecular; D017434:Protein Structure, Tertiary; D015375:Receptors, Interleukin-2 / Q000235:genetics / Q000378:metabolism; D053628:Receptors, Thrombopoietin / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction; D013601:T-Lymphocytes / Q000201:enzymology*; D053634:TYK2 Kinase / Q000737:chemistry* / Q000235:genetics
chemical_list: D015375:Receptors, Interleukin-2; D053628:Receptors, Thrombopoietin; C082218:MPL protein, human; C507904:JAK1 protein, human; C507933:JAK3 protein, human; D053613:Janus Kinase 1; D053616:Janus Kinase 3; D053634:TYK2 Kinase; C070139:TYK2 protein, human
keywords: Allosteric Regulation; Janus Kinase (JAK); Molecular Pharmacology; Pseudokinase; Signal Transduction; Structural Biology