title: Arfs at a glance.
abstract: The Arf small G proteins regulate protein and lipid trafficking in eukaryotic cells through a regulated cycle of GTP binding and hydrolysis. In their GTP-bound form, Arf proteins recruit a specific set of protein effectors to the membrane surface. These effectors function in vesicle formation and tethering, non-vesicular lipid transport and cytoskeletal regulation. Beyond fundamental membrane trafficking roles, Arf proteins also regulate mitosis, plasma membrane signaling, cilary trafficking and lipid droplet function. Tight spatial and temporal regulation of the relatively small number of Arf proteins is achieved by their guanine nucleotide-exchange factors (GEFs) and GTPase-activating proteins (GAPs), which catalyze GTP binding and hydrolysis, respectively. A unifying function of Arf proteins, performed in conjunction with their regulators and effectors, is sensing, modulating and transporting the lipids that make up cellular membranes. In this Cell Science at a Glance article and the accompanying poster, we discuss the unique features of Arf small G proteins, their functions in vesicular and lipid trafficking in cells, and how these functions are modulated by their regulators, the GEFs and GAPs. We also discuss how these Arf functions are subverted by human pathogens and disease states.
authors.affiliation: Membrane Dynamics and Intracellular Trafficking, Institut Jacques Monod, CNRS, UMR 7592, Université Paris Diderot, Sorbonne Paris Cité, F-75013 Paris, France jackson@ijm.univ-paris-diderot.fr.
authors.forename: Catherine L
authors.initials: CL
authors.lastname: Jackson
authors.affiliation: Membrane Dynamics and Intracellular Trafficking, Institut Jacques Monod, CNRS, UMR 7592, Université Paris Diderot, Sorbonne Paris Cité, F-75013 Paris, France.
authors.forename: Samuel
authors.initials: S
authors.lastname: Bouvet
mesh_terms: D020727:ADP-Ribosylation Factors / Q000378:metabolism*; D000818:Animals; D020690:GTPase-Activating Proteins / Q000378:metabolism*; D006801:Humans; D020559:Monomeric GTP-Binding Proteins / Q000378:metabolism*; D015398:Signal Transduction
chemical_list: D020690:GTPase-Activating Proteins; D020727:ADP-Ribosylation Factors; D020559:Monomeric GTP-Binding Proteins
keywords: Arf small GTP-binding protein; Golgi; Lipid transport; Membrane contact site; Plasma membrane; Vesicle trafficking