Arfaptins are localized to the trans-Golgi by interaction with Arl1, but not Arfs

J Biol Chem. 2011 Apr 1;286(13):11569-78. doi: 10.1074/jbc.M110.201442. Epub 2011 Jan 14.

Abstract

Arfaptins (arfaptin-1 and arfaptin-2/POR1) were originally identified as binding partners of the Arf small GTPases. Both proteins contain a BAR (Bin/Amphiphysin/Rvs) domain, which participates in membrane deformation. Here we show that arfaptins associate with trans-Golgi membranes. Unexpectedly, Arl1 (Arf-like 1), but not Arfs, determines the trans-Golgi association of arfaptins. We also demonstrate that arfaptins interact with Arl1 through their BAR domain-containing region and compete for Arl1 binding with golgin-97 and golgin-245/p230, both of which also bind to Arl1 through their GRIP (golgin-97/RanBP2/Imh1p/p230) domains. However, arfaptins and these golgins show only limited colocalization at the trans-Golgi. Time-lapse imaging of cells overexpressing fluorescent protein-tagged arfaptins and golgin-97 reveals that arfaptins, but not golgin-97, are included in vesicular and tubular structures emanating from the Golgi region. These observations indicate that arfaptins are recruited onto trans-Golgi membranes by interacting with Arl1, and capable of inducing membrane deformation via their BAR domains.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • ADP-Ribosylation Factors / genetics
  • ADP-Ribosylation Factors / metabolism*
  • Adaptor Proteins, Signal Transducing / genetics
  • Adaptor Proteins, Signal Transducing / metabolism*
  • Autoantigens / genetics
  • Autoantigens / metabolism
  • Golgi Apparatus / genetics
  • Golgi Apparatus / metabolism*
  • Golgi Matrix Proteins
  • HeLa Cells
  • Humans
  • Intracellular Membranes / metabolism*
  • Membrane Proteins / genetics
  • Membrane Proteins / metabolism*
  • Protein Structure, Tertiary / physiology

Substances

  • ARFIP1 protein, human
  • ARFIP2 protein, human
  • Adaptor Proteins, Signal Transducing
  • Autoantigens
  • GOLGA4 protein, human
  • Golgi Matrix Proteins
  • Golgi complex autoantigen, 97-kDa
  • Membrane Proteins
  • ADP-ribosylation factor related proteins
  • ADP-Ribosylation Factors