Reversible, allosteric small-molecule inhibitors of regulator of G protein signaling proteins

Levi L Blazer; David L Roman; Alfred Chung; Martha J Larsen; Benjamin M Greedy; Stephen M Husbands; Richard R Neubig

doi:10.1124/mol.110.065128

Back

Reversible, allosteric small-molecule inhibitors of regulator of G protein signaling proteins

Journal article

Open access

Peer reviewed

Reversible, allosteric small-molecule inhibitors of regulator of G protein signaling proteins

Levi L Blazer, David L Roman, Alfred Chung, Martha J Larsen, Benjamin M Greedy, Stephen M Husbands and Richard R Neubig

Molecular pharmacology, Vol.78(3), pp.524-533

09/2010

DOI: 10.1124/mol.110.065128

PMCID: PMC2939488

PMID: 20571077

Files and links (1)

url

https://doi.org/10.1124/mol.110.065128View

Published (Version of record) Open Access

Abstract

Regulators of G protein signaling (RGS) proteins are potent negative modulators of G protein signaling and have been proposed as potential targets for small-molecule inhibitor development. We report a high-throughput time-resolved fluorescence resonance energy transfer screen to identify inhibitors of RGS4 and describe the first reversible small-molecule inhibitors of an RGS protein. Two closely related compounds, typified by CCG-63802 [((2E)-2-(1,3-benzothiazol-2-yl)-3-[9-methyl-2-(3-methylphenoxy)-4-oxo-4H-pyrido[1,2-a]pyrimidin-3-yl]prop-2-enenitrile)], inhibit the interaction between RGS4 and Galpha(o) with an IC(50) value in the low micromolar range. They show selectivity among RGS proteins with a potency order of RGS 4 > 19 = 16 > 8 >> 7. The compounds inhibit the GTPase accelerating protein activity of RGS4, and thermal stability studies demonstrate binding to the RGS but not to Galpha(o). On RGS4, they depend on an interaction with one or more cysteines in a pocket that has previously been identified as an allosteric site for RGS regulation by acidic phospholipids. Unlike previous small-molecule RGS inhibitors identified to date, these compounds retain substantial activity under reducing conditions and are fully reversible on the 10-min time scale. CCG-63802 and related analogs represent a useful step toward the development of chemical tools for the study of RGS physiology.

Signal Transduction

Phospholipids - antagonists & inhibitors

GTP-Binding Proteins - antagonists & inhibitors

GTPase-Activating Proteins - antagonists & inhibitors

Humans

Cysteine - chemistry

GTPase-Activating Proteins - chemistry

GTPase-Activating Proteins - metabolism

Proteins - metabolism

Cysteine - antagonists & inhibitors

RGS Proteins - chemistry

Fluorescence Resonance Energy Transfer

RGS Proteins - metabolism

RGS Proteins - antagonists & inhibitors

Proteins - antagonists & inhibitors

GTP-Binding Proteins - metabolism

Details

Title: Subtitle: Reversible, allosteric small-molecule inhibitors of regulator of G protein signaling proteins
Creators: Levi L Blazer - Department of Pharmacology, University of Michigan, Ann Arbor, Michigan 48109, USA
David L Roman
Alfred Chung
Martha J Larsen
Benjamin M Greedy
Stephen M Husbands
Richard R Neubig
Resource Type: Journal article
Publication Details: Molecular pharmacology, Vol.78(3), pp.524-533
Publisher: United States
DOI: 10.1124/mol.110.065128
PMID: 20571077
PMCID: PMC2939488
ISSN: 0026-895X
eISSN: 1521-0111
Grant note: T32-GM00008597 / NIGMS NIH HHS P30 DK020572 / NIDDK NIH HHS R01-DA023252 / NIDA NIH HHS P60 DK020572 / NIDDK NIH HHS F32 GM076821 / NIGMS NIH HHS T32 GM008597 / NIGMS NIH HHS DK020572 / NIDDK NIH HHS F32-GM076821 / NIGMS NIH HHS R01 DA023252 / NIDA NIH HHS
Language: English
Date published: 09/2010
Academic Unit: Pharmacy; Iowa Neuroscience Institute; Pharmaceutical Sciences and Experimental Therapeutics; Medicinal and Natural Products Chemistry
Record Identifier: 9984065486002771

Metrics

15 Record Views

65 Times Cited - Web of Science

See more details