PDBsum entry 2w2v

Signaling protein

PDB id: 2w2v

Contents

Protein chains

171 a.a. *

170 a.a. *

161 a.a. *

Ligands

GTP ×4

Waters ×527

* Residue conservation analysis

PDB id:

2w2v

Name:

Signaling protein

Title:

Rac2 (g12v) in complex with gtpgs

Structure:

Ras-related c3 botulinum toxin substrate 2. Chain: a, b, c, d. Fragment: residues 1-177. Synonym: rac2, p21-rac2, small g protein, gx. Engineered: yes. Mutation: yes

Source:

Homo sapiens. Human. Organism_taxid: 9606. Expressed in: spodoptera frugiperda. Expression_system_taxid: 7108. Expression_system_cell_line: sf9.

Resolution:

2.00Å R-factor: 0.283 R-free: 0.345

Authors:

O.Opaleye,T.D.Bunney,S.M.Roe,L.H.Pearl

Key ref:

T.D.Bunney et al. (2009). Structural insights into formation of an active signaling complex between Rac and phospholipase C gamma 2. Mol Cell, 34, 223-233. PubMed id: 19394299 DOI: 10.1016/j.molcel.2009.02.023

Date:

04-Nov-08 Release date: 05-May-09

Protein chains

P15153  (RAC2_HUMAN) -  Ras-related C3 botulinum toxin substrate 2 from Homo sapiens

Seq: 192 a.a.

Struc: 171 a.a.*

Protein chain

P15153  (RAC2_HUMAN) -  Ras-related C3 botulinum toxin substrate 2 from Homo sapiens

Seq: 192 a.a.

Struc: 170 a.a.*

Protein chain

P15153  (RAC2_HUMAN) -  Ras-related C3 botulinum toxin substrate 2 from Homo sapiens

Seq: 192 a.a.

Struc: 161 a.a.*

* PDB and UniProt seqs differ at 3 residue positions (black crosses)

Enzyme reactions

• Enzyme class: Chains A, B, C, D: E.C.?

DOI no: 10.1016/j.molcel.2009.02.023

Mol Cell 34:223-233 (2009)

PubMed id: 19394299

Structural insights into formation of an active signaling complex between Rac and phospholipase C gamma 2.

T.D.Bunney, O.Opaleye, S.M.Roe, P.Vatter, R.W.Baxendale, C.Walliser, K.L.Everett, M.B.Josephs, C.Christow, F.Rodrigues-Lima, P.Gierschik, L.H.Pearl, M.Katan.

ABSTRACT

Rho family GTPases are important cellular switches and control a number of physiological functions. Understanding the molecular basis of interaction of these GTPases with their effectors is crucial in understanding their functions in the cell. Here we present the crystal structure of the complex of Rac2 bound to the split pleckstrin homology (spPH) domain of phospholipase C-gamma(2) (PLCgamma(2)). Based on this structure, we illustrate distinct requirements for PLCgamma(2) activation by Rac and EGF and generate Rac effector mutants that specifically block activation of PLCgamma(2), but not the related PLCbeta(2) isoform. Furthermore, in addition to the complex, we report the crystal structures of free spPH and Rac2 bound to GDP and GTPgammaS. These structures illustrate a mechanism of conformational switches that accompany formation of signaling active complexes and highlight the role of effector binding as a common feature of Rac and Cdc42 interactions with a variety of effectors.

Selected figure(s)

Figure 1.
Figure 1. Crystal Structure of the Rac2^G12V(GTPγS)/PLCγ[2]spPH Complex
Domain organization of PLCγ[2] (A) shows domains common to all families (nPH, EF-hands, catalytic, and C2) and domains specific to PLCγ family (nSH2, cSH2, SH3, and spPH); spPH is shown in orange. Overview of the Rac2^G12V(2-177) GTPγS/PLCγ[2]spPH complex structure (B). Surface topology (shown as translucent surfaces) and ribbon representation of the complex show the spPH domain in orange and the Rac2 molecule in blue. The Rac2 switch I region is shown in green, and the switch II region is shown in magenta. The GTPγS molecule bound to Rac2 is in ball-and-stick representation. Close-up of the interaction interface is viewed from the side with important amino acid residues of both Rac2 and spPH represented as ball and sticks (C). Also shown is a close-up from above with important Rac2 amino acid residues (ball-and-stick representation) and the spPH surface (D). The hydrophobic cleft into which Rac2 residues Val36 and Phe37 protrude can be clearly seen. The summary of interactions at the interface is illustrated schematically highlighting the predominant types of bonding between the two species in the complex (E).

Figure 6.
Figure 6. Effector-Facilitated Conformational Changes in Rac/Cdc42 Proteins
Comparison of switch I regions of uncomplexed, GTP analog-bound Ras (pdb: 121P) (A) with an overlay of Rac2 and Cdc42 uncomplexed, GTP analog-bound structures (pdb: 2w2v and 2QRZ) ([B], left) and Rac2 and Cdc42 GTP analog-bound structures (overlay) from complexes with PLCγ[2] (pdb: 2w2x) and Par6 (pdb: 1NF3), respectively ([B], right). Conformations of switch I region and orientation of indicated key residues in free Rac/CDC42-(GTP) proteins and in complexes with their effectors are clearly different. Binding of several effectors to Rac/Cdc42 proteins involves interaction with switch I residues Val36 and Phe37 that stabilizes signaling-active (state 2) conformation where other switch I residues, Thr35 and Tyr32, can coordinate γ-phosphate of GTP.

The above figures are reprinted by permission from Cell Press: Mol Cell (2009, 34, 223-233) copyright 2009.

Figures were selected by an automated process.