Both stimulatory and inhibitory GDP/GTP exchange proteins, smg GDS and rho GDI, are active on multiple small GTP-binding proteins.
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.
Hiraoka
K
K
Department of Biochemistry, Kobe University School of Medicine, Japan.
Kaibuchi
K
K
Ando
S
S
Musha
T
T
Takaishi
K
K
Mizuno
T
T
Asada
M
M
Ménard
L
L
Tomhave
E
E
Didsbury
J
J
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
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