title: A yeast GTPase-activating protein that interacts specifically with a member of the Ypt/Rab family.
abstract: Members of the Ras superfamily of GTP-binding proteins are involved in a variety of cellular processes, including signal transduction, cytoskeletal organization and protein transport. GTP-binding proteins of the Ypt/Rab family direct vesicular protein transport in the secretory and endocytic pathways in the yeast Saccharomyces cerevisiae (Ypt proteins) and in mammalian systems (Rab proteins). The cellular activity of monomeric GTP-binding proteins is influenced by proteins that regulate GDP/GTP exchange and GTP hydrolysis. GTPase-activating proteins (GAPs) can increase the slow intrinsic GTPase activity of GTP-binding proteins by several orders of magnitude. As GAPs modulate the activity of GTP-binding proteins, they are thought to give a biochemical handle on the functioning of Ypt/Rab proteins in transport vesicle budding and docking or fusion at donor and acceptor membranes. We report here the first cloned GTPase-activating protein for the Ypt/Rab protein family. The gene, GYP6 (GAP of Ypt6 protein), encodes a protein of 458 amino acids which is highly specific for the Ypt6 protein and shows little or no cross-reactivity with other Ypt/Rab family members or with H-Ras p21.
authors.affiliation: Department of Molecular Genetics, Max-Planck Institute of Biophysical Chemistry, Göttingen, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Strom
authors.forename: P
authors.initials: P
authors.lastname: Vollmer
authors.forename: T J
authors.initials: TJ
authors.lastname: Tan
authors.forename: D
authors.initials: D
authors.lastname: Gallwitz
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D003001:Cloning, Molecular; D004271:DNA, Fungal / Q000235:genetics / Q000302:isolation & purification; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism*; D019204:GTP-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D020690:GTPase-Activating Proteins; D005800:Genes, Fungal; D006160:Guanosine Triphosphate / Q000378:metabolism; D007700:Kinetics; D008322:Mammals; D008969:Molecular Sequence Data; D011494:Protein Kinases / Q000235:genetics / Q000378:metabolism*; D011506:Proteins / Q000378:metabolism*; D016283:Proto-Oncogene Proteins p21(ras) / Q000235:genetics / Q000378:metabolism; D015183:Restriction Mapping; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins; D017386:Sequence Homology, Amino Acid; D020703:ras GTPase-Activating Proteins
chemical_list: D004271:DNA, Fungal; D005656:Fungal Proteins; D020690:GTPase-Activating Proteins; C079894:GYP6 protein, S cerevisiae; D011506:Proteins; D029701:Saccharomyces cerevisiae Proteins; D020703:ras GTPase-Activating Proteins; D006160:Guanosine Triphosphate; D011494:Protein Kinases; D019204:GTP-Binding Proteins; D016283:Proto-Oncogene Proteins p21(ras)