Abstract
The Rho guanosine 5'-triphosphatase (GTPase) cycles between the active guanosine triphosphate (GTP)-bound form and the inactive guanosine diphosphate-bound form and regulates cell adhesion and cytokinesis, but how it exerts these actions is unknown. The yeast two-hybrid system was used to clone a complementary DNA for a protein (designated Rhophilin) that specifically bound to GTP-Rho. The Rho-binding domain of this protein has 40 percent identity with a putative regulatory domain of a protein kinase, PKN. PKN itself bound to GTP-Rho and was activated by this binding both in vitro and in vivo. This study indicates that a serine-threonine protein kinase is a Rho effector and presents an amino acid sequence motif for binding to GTP-Rho that may be shared by a family of Rho target proteins.
Publication types
-
Research Support, Non-U.S. Gov't
MeSH terms
-
Adaptor Proteins, Signal Transducing
-
Amino Acid Sequence
-
Animals
-
Cell Line
-
Cloning, Molecular
-
Enzyme Activation
-
GTP Phosphohydrolases / metabolism*
-
GTP-Binding Proteins / chemistry
-
GTP-Binding Proteins / metabolism*
-
Guanosine Triphosphate / metabolism
-
Humans
-
Membrane Proteins / metabolism*
-
Mice
-
Molecular Sequence Data
-
Phosphorylation
-
Protein Kinase C / chemistry
-
Protein Kinase C / metabolism*
-
Protein Serine-Threonine Kinases*
-
Recombinant Fusion Proteins / metabolism
-
Saccharomyces cerevisiae / genetics
-
Signal Transduction
-
ras Proteins
-
rho GTP-Binding Proteins*
-
rhoA GTP-Binding Protein
-
rhoB GTP-Binding Protein
-
rhoC GTP-Binding Protein
Substances
-
Adaptor Proteins, Signal Transducing
-
Membrane Proteins
-
Recombinant Fusion Proteins
-
rhophilin
-
Guanosine Triphosphate
-
protein kinase N
-
Protein Serine-Threonine Kinases
-
Protein Kinase C
-
GTP Phosphohydrolases
-
GTP-Binding Proteins
-
RHOC protein, human
-
Rhoc protein, mouse
-
ras Proteins
-
rho GTP-Binding Proteins
-
rhoA GTP-Binding Protein
-
rhoB GTP-Binding Protein
-
rhoC GTP-Binding Protein