Structural basis for the selective activation of Rho GTPases by Dbl exchange factors

Jason T Snyder; David K Worthylake; Kent L Rossman; Laurie Betts; Wendy M Pruitt; David P Siderovski; Channing J Der; John Sondek

doi:10.1038/nsb796

Structural basis for the selective activation of Rho GTPases by Dbl exchange factors

Nat Struct Biol. 2002 Jun;9(6):468-75. doi: 10.1038/nsb796.

Authors

Jason T Snyder¹, David K Worthylake, Kent L Rossman, Laurie Betts, Wendy M Pruitt, David P Siderovski, Channing J Der, John Sondek

Affiliation

¹ Department of Biochemistry and Biophysics, Program in Molecular and Cellular Biophysics, Chapel Hill, North Carolina 27599, USA.

PMID: 12006984
DOI: 10.1038/nsb796

Abstract

Activation of Rho-family GTPases involves the removal of bound GDP and the subsequent loading of GTP, all catalyzed by guanine nucleotide exchange factors (GEFs) of the Dbl-family. Despite high sequence conservation among Rho GTPases, Dbl proteins possess a wide spectrum of discriminatory potentials for Rho-family members. To rationalize this specificity, we have determined crystal structures of the conserved, catalytic fragments (Dbl and pleckstrin homology domains) of the exchange factors intersectin and Dbs in complex with their cognate GTPases, Cdc42 and RhoA, respectively. Structure-based mutagenesis of intersectin and Dbs reveals the key determinants responsible for promoting exchange activity in Cdc42, Rac1 and RhoA. These findings provide critical insight into the structural features necessary for the proper pairing of Dbl-exchange factors with Rho GTPases and now allow for the detailed manipulation of signaling pathways mediated by these oncoproteins in vivo.

Publication types

Research Support, Non-U.S. Gov't
Research Support, U.S. Gov't, P.H.S.

MeSH terms

Amino Acid Sequence
Crystallography, X-Ray
Enzyme Activation
Guanine Nucleotide Exchange Factors / chemistry*
Guanine Nucleotide Exchange Factors / metabolism*
Guanosine Triphosphate / metabolism
Humans
Models, Molecular
Molecular Sequence Data
Protein Structure, Secondary
Protein Structure, Tertiary
Proteins / chemistry
Proteins / metabolism
Proto-Oncogene Proteins / chemistry*
Sequence Alignment
Structure-Activity Relationship
Substrate Specificity
T-Lymphoma Invasion and Metastasis-inducing Protein 1
cdc42 GTP-Binding Protein / chemistry
cdc42 GTP-Binding Protein / metabolism
rac1 GTP-Binding Protein / chemistry
rac1 GTP-Binding Protein / metabolism
rho GTP-Binding Proteins / chemistry*
rho GTP-Binding Proteins / metabolism*
rhoA GTP-Binding Protein / chemistry
rhoA GTP-Binding Protein / metabolism

Substances

Guanine Nucleotide Exchange Factors
MCF2 protein, human
Proteins
Proto-Oncogene Proteins
T-Lymphoma Invasion and Metastasis-inducing Protein 1
TIAM1 protein, human
Guanosine Triphosphate
cdc42 GTP-Binding Protein
rac1 GTP-Binding Protein
rho GTP-Binding Proteins
rhoA GTP-Binding Protein

Associated data

PDB/1KI1
PDB/1LB1