title: Arf GAPs as regulators of the actin cytoskeleton.
abstract: The Arf (ADP-ribosylation factor) GAPs (GTPase-activating proteins) are a family of proteins with a common catalytic domain that induces hydrolysis of GTP bound to Arf GTP-binding proteins. At least three groups of multidomain Arf GAPs affect the actin cytoskeleton and cellular activities, such as migration and movement, that depend on the cytoskeleton. One role of the Arf GAPs is to regulate membrane remodelling that accompanies actin polymerization. Regulation of membrane remodelling is mediated in part by the regulation of Arf proteins. However, Arf GAPs also regulate actin independently of effects on membranes or Arf. These functions include acting as upstream regulators of Rho family proteins and providing a scaffold for Rho effectors and exchange factors. With multiple functional elements, the Arf GAPs could integrate signals and biochemical activities that result in co-ordinated changes in actin and membranes necessary for a wide range of cellular functions.
authors.affiliation: Laboratory of Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892, USA. randazzo@helix.nih.gov
authors.forename: Paul A
authors.initials: PA
authors.lastname: Randazzo
authors.forename: Hiroki
authors.initials: H
authors.lastname: Inoue
authors.forename: Sanita
authors.initials: S
authors.lastname: Bharti
mesh_terms: D020727:ADP-Ribosylation Factors / Q000235:genetics / Q000378:metabolism*; D000199:Actins / Q000378:metabolism*; D048868:Adaptor Proteins, Signal Transducing / Q000378:metabolism; D000818:Animals; D002352:Carrier Proteins / Q000378:metabolism; D002460:Cell Line; D003599:Cytoskeleton / Q000378:metabolism* / Q000648:ultrastructure; D020690:GTPase-Activating Proteins / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D009474:Neurons / Q000166:cytology / Q000378:metabolism; D051419:Paxillin / Q000378:metabolism; D015398:Signal Transduction / Q000502:physiology; D013379:Substrate Specificity; D020741:rho GTP-Binding Proteins / Q000378:metabolism
chemical_list: C446514:ARAP2 protein, human; D000199:Actins; D048868:Adaptor Proteins, Signal Transducing; C485546:Asap1 protein, mouse; D002352:Carrier Proteins; D020690:GTPase-Activating Proteins; D051419:Paxillin; D020727:ADP-Ribosylation Factors; D020741:rho GTP-Binding Proteins