PDBsum entry: 1cee

Structural protein regulation

PDB id: 1cee

Contents

Protein chains

179 a.a. *

59 a.a. *

Ligands

GCP

Metals

_MG

* Residue conservation analysis

PDB id:

1cee

Name:

Structural protein regulation

Title:

Solution structure of cdc42 in complex with the gtpase binding domain of wasp

Structure:

Gtp-binding rho-like protein. Chain: a. Fragment: cdc42. Synonym: cell division cycle 42, pcdc42. Engineered: yes. Wiskott-aldrich syndrome protein wasp. Chain: b. Fragment: gtpase binding domain of wasp. Engineered: yes

Source:

Homo sapiens. Human. Organism_taxid: 9606. Expressed in: escherichia coli bl21(de3). Expression_system_taxid: 469008.

NMR struc:

20 models

Authors:

N.Abdul-Manan,B.Aghazadeh,G.A.Liu,A.Majumdar,O.Ouerfelli, M.K.Rosen

Key ref:

N.Abdul-Manan et al. (1999). Structure of Cdc42 in complex with the GTPase-binding domain of the 'Wiskott-Aldrich syndrome' protein. Nature, 399, 379-383. PubMed id: 10360578 DOI: 10.1038/20726

Date:

08-Mar-99 Release date: 30-Jun-99

Protein chain

P60953  (CDC42_HUMAN) -  Cell division control protein 42 homolog

Seq: 191 a.a.

Struc: 179 a.a.

Protein chain

P42768  (WASP_HUMAN) -  Wiskott-Aldrich syndrome protein

Seq: 502 a.a.

Struc: 59 a.a.

 Gene Ontology (GO) functional annotation 

• Cellular component: mitotic spindle (13 terms)
• Biological process: positive regulation of cell cycle cytokinesis (22 terms)
• Biochemical function: nucleotide binding (6 terms)

DOI no: 10.1038/20726

Nature 399:379-383 (1999)

PubMed id: 10360578

Structure of Cdc42 in complex with the GTPase-binding domain of the 'Wiskott-Aldrich syndrome' protein.

N.Abdul-Manan, B.Aghazadeh, G.A.Liu, A.Majumdar, O.Ouerfelli, K.A.Siminovitch, M.K.Rosen.

ABSTRACT

The Rho-family GTP-hydrolysing proteins (GTPases), Cdc42, Rac and Rho, act as molecular switches in signalling pathways that regulate cytoskeletal architecture, gene expression and progression of the cell cycle. Cdc42 and Rac transmit many signals through GTP-dependent binding to effector proteins containing a Cdc42/Rac-interactive-binding (CRIB) motif. One such effector, the Wiskott-Aldrich syndrome protein (WASP), is postulated to link activation of Cdc42 directly to the rearrangement of actin. Human mutations in WASP cause severe defects in haematopoletic cell function, leading to clinical symptoms of thrombocytopenia, immunodeficiency and eczema. Here we report the solution structure of a complex between activated Cdc42 and a minimal GTPase-binding domain (GBD) from WASP. An extended amino-terminal GBD peptide that includes the CRIB motif contacts the switch I, beta2 and alpha5 regions of Cdc42. A carboxy-terminal beta-hairpin and alpha-helix pack against switch II. The Phe-X-His-X2-His portion of the CRIB motif and the alpha-helix appear to mediate sensitivity to the nucleotide switch through contacts to residues 36-40 of Cdc42. Discrimination between the Rho-family members is likely to be governed by GBD contacts to the switch I and alpha5 regions of the GTPases. Structural and biochemical data suggest that GBD-sequence divergence outside the CRIB motif may reflect additional regulatory interactions with functional domains that are specific to individual effectors.

Selected figure(s)

Figure 2.
Figure 2: GTPase–effector interactions. a, Ribbons^30 depiction of a representative conformer from the final ensemble of structures of the Cdc42 (blue)/WASP (yellow) complex. Switch I (residues 32–40) and switch II (residues 60–70) of Cdc42 are red. CRIB motif of WASP is white. b, Rap1A/Raf complex^5 coloured as in a. Nucleotide and Mg^2+ in a and b are displayed as ball and stick models. c, Contacts between WASP (yellow with red side chains) and the switch I, switch II and 3 regions of Cdc42 (blue with green side chains). Intermolecular main-chain hydrogen bonds observed in most members of the NMR ensemble are indicated by dashed lines. Nucleotide not shown. d, Interaction of the WASP GBD N terminus and the Cdc42 2/ 3 hairpin and 5 helix, coloured as in c. Intramolecular hydrogen bonds between GBD residues 234 and 237 are indicated by dashed lines.

Figure 3.
Figure 3: Selected regions of a ^13C-filtered NOESY spectrum recorded in D[2]O. Intermolecular NOEs are shown to the C^ 1H[3] methyl groups of a, Leu 67, and b, Leu 70 of Cdc42. Unambiguous WASP assignments are indicated on the side. Inset in a displays NOEs from Leu 67 C^ 1H[3] to aromatic protons of WASP observed in an analogous spectrum recorded on a complex between ^13C-labelled, methyl-protonated but otherwise deuterated, Cdc42 and unlabelled WASP.

The above figures are reprinted by permission from Macmillan Publishers Ltd: Nature (1999, 399, 379-383) copyright 1999.

Figures were selected by an automated process.