title: Both stimulatory and inhibitory GDP/GTP exchange proteins, smg GDS and rho GDI, are active on multiple small GTP-binding proteins.
abstract: Six peaks of small GTP-binding proteins (G proteins) were separated by column chromatographies from the cytosol fraction of the differentiated HL-60 cells: two peaks of rho p21, one peak of smg/rap1 p21, two peaks of rac1 p21, and one peak of an unidentified small G protein with a Mr of about 20,000 (20 KG). smg GDS, previously thought to be a stimulatory GDP/GTP exchange protein for smg p21, Ki-ras p21, and rho p21, but not for Ha-ras p21 or smg p25A, was also active on rac1 p21. rho GDI, previously thought to be an inhibitory GDP/GTP exchange protein specific for rho p21, was also active on rac1 p21. These results indicate that both smg GDS and rho GDI are active on multiple small G proteins.
authors.affiliation: Department of Biochemistry, Kobe University School of Medicine, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Hiraoka
authors.forename: K
authors.initials: K
authors.lastname: Kaibuchi
authors.forename: S
authors.initials: S
authors.lastname: Ando
authors.forename: T
authors.initials: T
authors.lastname: Musha
authors.forename: K
authors.initials: K
authors.lastname: Takaishi
authors.forename: T
authors.initials: T
authors.lastname: Mizuno
authors.forename: M
authors.initials: M
authors.lastname: Asada
authors.forename: L
authors.initials: L
authors.lastname: Ménard
authors.forename: E
authors.initials: E
authors.lastname: Tomhave
authors.forename: J
authors.initials: J
authors.lastname: Didsbury
mesh_terms: D002454:Cell Differentiation; D002460:Cell Line; D002852:Chromatography, Ion Exchange; D003600:Cytosol / Q000378:metabolism; D019204:GTP-Binding Proteins / Q000302:isolation & purification / Q000378:metabolism*; D020730:Guanine Nucleotide Dissociation Inhibitors; D016244:Guanosine 5'-O-(3-Thiotriphosphate) / Q000378:metabolism; D006153:Guanosine Diphosphate / Q000378:metabolism; D006801:Humans; D015151:Immunoblotting; D007700:Kinetics; D015473:Leukemia, Promyelocytic, Acute; D020668:rap GTP-Binding Proteins; D062947:rho-Specific Guanine Nucleotide Dissociation Inhibitors
chemical_list: D020730:Guanine Nucleotide Dissociation Inhibitors; D062947:rho-Specific Guanine Nucleotide Dissociation Inhibitors; D006153:Guanosine Diphosphate; D016244:Guanosine 5'-O-(3-Thiotriphosphate); D019204:GTP-Binding Proteins; D020668:rap GTP-Binding Proteins