title: A SMAP gene family encoding ARF GTPase-activating proteins and its implication in membrane trafficking.
abstract: SMAP1 and SMAP2 proteins constitute a subfamily of the Arf-specific GTPase-activating proteins. Both SMAP proteins bind to clathrin heavy chains and are involved in the trafficking of clathrin-coated vesicles. In cells, SMAP1 regulates Arf6-dependent endocytosis of transferrin receptors from the coated pits of the plasma membrane, whereas SMAP2 regulates Arf1-dependent retrograde transport of TGN38 from the early endosome to the trans-Golgi network. The common and distinct features of SMAP1 and SMAP2 activity provide a valuable opportunity to examine the differential regulation of membrane trafficking by these two proteins. In this chapter, we describe several basic experimental procedures that have been used to study the regulation of membrane trafficking using SMAP proteins, including a GAP assay as well as procedures to study the transport of transferrin receptors and TGN38. In addition, a yeast two-hybrid system is described because of its utility in identifying novel molecules that interact with SMAP.
authors.affiliation: Department of Molecular Immunology, Institute of Development, Aging and Cancer, Tohoku University, Sendai, Japan.
authors.forename: Kenji
authors.initials: K
authors.lastname: Tanabe
authors.forename: Shunsuke
authors.initials: S
authors.lastname: Kon
authors.forename: Nobuyuki
authors.initials: N
authors.lastname: Ichijo
authors.forename: Tomo
authors.initials: T
authors.lastname: Funaki
authors.forename: Waka
authors.initials: W
authors.lastname: Natsume
authors.forename: Toshio
authors.initials: T
authors.lastname: Watanabe
authors.forename: Masanobu
authors.initials: M
authors.lastname: Satake
mesh_terms: D000089982:ADP-Ribosylation Factor 6; D020727:ADP-Ribosylation Factors / Q000378:metabolism; D000595:Amino Acid Sequence; D000818:Animals; D019556:COS Cells; D015820:Cadherins / Q000378:metabolism; D002522:Chlorocebus aethiops; D020690:GTPase-Activating Proteins / Q000378:metabolism*; D006801:Humans; D006834:Hydrazines; D053645:Interleukin-2 Receptor alpha Subunit / Q000378:metabolism; D008562:Membrane Glycoproteins / Q000378:metabolism; D008565:Membrane Proteins / Q000378:metabolism*; D051379:Mice; D008969:Molecular Sequence Data; D021381:Protein Transport / Q000502:physiology*; D011719:Pyrazines; D011804:Quinolines; D016415:Sequence Alignment; D025841:Small Ubiquitin-Related Modifier Proteins / Q000378:metabolism; D014168:Transferrin / Q000378:metabolism; D020798:Two-Hybrid System Techniques
chemical_list: D000089982:ADP-Ribosylation Factor 6; C503238:Arfgap1 protein, mouse; D015820:Cadherins; D020690:GTPase-Activating Proteins; D006834:Hydrazines; D053645:Interleukin-2 Receptor alpha Subunit; D008562:Membrane Glycoproteins; D008565:Membrane Proteins; D011719:Pyrazines; C504331:QU663 compound; D011804:Quinolines; C529588:SMAP2 protein, mouse; D025841:Small Ubiquitin-Related Modifier Proteins; C484577:Smap1 protein, mouse; C072237:TGOLN2 protein, human; D014168:Transferrin; D020727:ADP-Ribosylation Factors; C000715348:ARF6 protein, human; C000715727:Arf6 protein, mouse