title: A small molecule-regulated guanine nucleotide exchange factor.
abstract: Selective, pharmacological agents are attractive tools for studying signal transduction because they allow rapid, reversible, and dose-dependent control over intracellular protein function. However, for many targets the identification of potent and selective small molecule agonists and antagonists is a formidable challenge. An attractive strategy for circumventing this problem is to engineer a protein of interest to be sensitive to a pharmacological agent of choice. Here, we report a chemical genetic method for regulating the catalytic activity of signaling enzymes with a small molecule. This approach uses the interaction of the antiapoptotic protein Bcl-xL and a BH3 peptide as an autoinhibitory switch that can be controlled with a small molecule. We applied this strategy to the guanine nucleotide exchange factor Intersectin, which is a selective activator of the GTPase Cdc42. Replacing Intersectin's regulatory domains with the BH3 peptide/Bcl-xL binding module generated a panel of synthetic GEF constructs that can be activated with a competitive ligand. Importantly, the nucleotide exchange activities of these synthetic Intersectin constructs can be controlled in a rapid and dose-dependent manner. The modular nature of this strategy should make it useful for engineering other enzymes involved in signal transduction.
authors.affiliation: Department of Chemistry, University of Washington, Box 351700, Seattle, Washington 98195-1700, USA.
authors.forename: Inna
authors.initials: I
authors.lastname: Goreshnik
authors.forename: Dustin J
authors.initials: DJ
authors.lastname: Maly
mesh_terms: D000814:Aniline Compounds / Q000494:pharmacology; D001665:Binding Sites; D001713:Biphenyl Compounds / Q000494:pharmacology; D020662:Guanine Nucleotide Exchange Factors / Q000737:chemistry / Q000378:metabolism*; D015394:Molecular Structure; D008970:Molecular Weight; D009596:Nitrophenols / Q000494:pharmacology; D010446:Peptide Fragments / Q000037:antagonists & inhibitors / Q000737:chemistry / Q000378:metabolism; D010879:Piperazines / Q000494:pharmacology; D011485:Protein Binding; D011518:Proto-Oncogene Proteins / Q000037:antagonists & inhibitors / Q000737:chemistry / Q000378:metabolism; D064067:Rho Guanine Nucleotide Exchange Factors; D013329:Structure-Activity Relationship; D013449:Sulfonamides / Q000494:pharmacology; D051020:bcl-X Protein / Q000037:antagonists & inhibitors / Q000737:chemistry / Q000378:metabolism; D000096926:Benzenesulfonamides
chemical_list: D000814:Aniline Compounds; D001713:Biphenyl Compounds; D020662:Guanine Nucleotide Exchange Factors; D009596:Nitrophenols; D010446:Peptide Fragments; D010879:Piperazines; D011518:Proto-Oncogene Proteins; D064067:Rho Guanine Nucleotide Exchange Factors; D013449:Sulfonamides; D051020:bcl-X Protein; C509000:4-(3-dimethylamino-1-phenylsulfanylmethylpropylamino)-N-(4-(4,4-dimethylpiperidin-1-yl)benzoyl)-3-nitrobenzenesulfonamide; D000096926:Benzenesulfonamides; C501332:ABT-737; C474007:Bax protein (53-86)