Identification and partial purification of GTPase-activating proteins from yeast and mammalian cells that preferentially act on Ypt1/Rab1 proteins.
Two GTPase-activating proteins of apparent molecular mass of 100 kDa and 30 kDa have been partially purified from porcine liver cytosol using mammalian Ypt1/Rab1 protein as substrate. Both proteins act most efficiently on Ypt1/Rab1p, but are inactive with H-Ras p21. From the budding yeast Saccharomyces cerevisiae, a cytosolic 40 kDa yptGAP was partially purified. It accelerates the intrinsic GTPase activity of wild-type Ypt1p but not of H-Ras p21 or a mutant ypt1p with an amino acid substitution of the effector domain which renders the protein functionally inactive in yeast cells.
Tan
T J
TJ
Department of Molecular Genetics, Max Planck Institute of Biophysical Chemistry, Göttingen, Germany.
Vollmer
P
P
Gallwitz
D
D
D000818:Animals; D003600:Cytosol / Q000201:enzymology; D005656:Fungal Proteins / Q000737:chemistry / Q000302:isolation & purification*; D019204:GTP-Binding Proteins / Q000737:chemistry / Q000302:isolation & purification*; D020690:GTPase-Activating Proteins; D008099:Liver / Q000201:enzymology; D051379:Mice; D008970:Molecular Weight; D011506:Proteins / Q000737:chemistry / Q000302:isolation & purification*; D012441:Saccharomyces cerevisiae / Q000201:enzymology*; D029701:Saccharomyces cerevisiae Proteins; D013379:Substrate Specificity; D013552:Swine; D020691:rab GTP-Binding Proteins; D020703:ras GTPase-Activating Proteins
D005656:Fungal Proteins; D020690:GTPase-Activating Proteins; D011506:Proteins; D029701:Saccharomyces cerevisiae Proteins; D020703:ras GTPase-Activating Proteins; D019204:GTP-Binding Proteins; C060755:YPT1 protein, S cerevisiae; D020691:rab GTP-Binding Proteins