PDBsum entry: 1t84

Signaling protein

PDB id: 1t84

Contents

Protein chain

107 a.a. *

Ligands

WSK

* Residue conservation analysis

PDB id:

1t84

Name:

Signaling protein

Title:

Solution structure of the wiskott-aldrich syndrome protein (wasp) autoinhibited core domain complexed with (s)- wiskostatin, a small molecule inhibitor

Structure:

Wiskott-aldrich syndrome protein. Chain: a. Fragment: core autoinhibited domain (gtpase binding domain is covalently linked to the cofilin homology and acidic regions). Synonym: wasp. Engineered: yes

Source:

Homo sapiens. Human. Organism_taxid: 9606. Gene: wasp (residues 242-310 and 461-492). Expressed in: escherichia coli bl21(de3). Expression_system_taxid: 469008.

NMR struc:

20 models

Authors:

J.R.Peterson,L.C.Bickford,D.Morgan,A.S.Kim,O.Ouerfelli, M.W.Kirschner,M.K.Rosen

Key ref:

J.R.Peterson et al. (2004). Chemical inhibition of N-WASP by stabilization of a native autoinhibited conformation. Nat Struct Mol Biol, 11, 747-755. PubMed id: 15235593 DOI: 10.1038/nsmb796

Date:

11-May-04 Release date: 13-Jul-04

Protein chain

P42768  (WASP_HUMAN) -  Wiskott-Aldrich syndrome protein

Seq: 502 a.a.

Struc: 107 a.a.*

* PDB and UniProt seqs differ at 35 residue positions (black crosses)

 Gene Ontology (GO) functional annotation 

• Cellular component: actin cytoskeleton (1 term)
• Biological process: protein complex assembly (2 terms)
• Biochemical function: protein binding (2 terms)

DOI no: 10.1038/nsmb796

Nat Struct Mol Biol 11:747-755 (2004)

PubMed id: 15235593

Chemical inhibition of N-WASP by stabilization of a native autoinhibited conformation.

J.R.Peterson, L.C.Bickford, D.Morgan, A.S.Kim, O.Ouerfelli, M.W.Kirschner, M.K.Rosen.

ABSTRACT

Current drug discovery efforts focus primarily on proteins with defined enzymatic or small molecule binding sites. Autoregulatory domains represent attractive alternative targets for small molecule inhibitors because they also occur in noncatalytic proteins and because allosteric inhibitors may avoid specificity problems inherent in active site-directed inhibitors. We report here the identification of wiskostatin, a chemical inhibitor of the neural Wiskott-Aldrich syndrome protein (N-WASP). Wiskostatin interacts with a cleft in the regulatory GTPase-binding domain (GBD) of WASP in the solution structure of the complex. Wiskostatin induces folding of the isolated, unstructured GBD into its autoinhibited conformation, suggesting that wiskostatin functions by stabilizing N-WASP in its autoinhibited state. The use of small molecules to bias conformational equilibria represents a potentially general strategy for chemical inhibition of autoinhibited proteins, even in cases where such sites have not been naturally evolved in a target.

Selected figure(s)

Figure 1.
Figure 1. Structure and regulation of the Wiskott-Aldrich syndrome protein family. (a) Domain structure of N-WASP, WASP and WASP constructs used in this study. The following functional domains are indicated: WH1 (WASP-homology 1) or EVH1 (Ena, vasodilator-stimulated phosphoprotein, or VASP-homology 1); a highly basic region (BR); the GTPase-binding domain (GBD); a proline-rich region; and a C-terminal VCA region (verprolin homology, central hydrophobic region, acidic region). WASP and N-WASP share 70% sequence identity over the residues included in mini-WASP. (b) Activation of WASP proteins by Cdc42 and PIP[2] requires the dissociation of an intramolecular autoinhibitory interaction between the GBD and VCA elements, allowing the VCA element to activate Arp2/3 complex.

Figure 2.
Figure 2. Structure and potency of wiskostatin and derivatives. (a) Dose-dependent inhibition of actin polymerization in cytoplasmic extract by (S)-wiskostatin. The increase in pyrene-actin fluorescence in response to PIP[2] addition reflects polymerization of pyrene-actin into filaments. The maximal rate of polymerization is inhibited by 50% in the presence of 5 M (S)-wiskostatin and almost completely by 10 M (S)-wiskostatin with respect to vehicle control (DMSO). Additional concentrations tested are not shown. (b) For each compound, the concentration required to inhibit the actin polymerization rate in PIP[2]-stimulated extract to 50% of the maximum control rate is shown. Atoms distinguishing control compounds from wiskostatin are in large print.

The above figures are reprinted by permission from Macmillan Publishers Ltd: Nat Struct Mol Biol (2004, 11, 747-755) copyright 2004.

Figures were selected by an automated process.