Arfophilins are dual Arf/Rab 11 binding proteins that regulate recycling endosome distribution and are related to Drosophila nuclear fallout

Mol Biol Cell. 2003 Jul;14(7):2908-20. doi: 10.1091/mbc.e03-03-0160. Epub 2003 Apr 17.

Abstract

Arfophilin is an ADP ribosylation factor (Arf) binding protein of unknown function. It is identical to the Rab11 binding protein eferin/Rab11-FIP3, and we show it binds both Arf5 and Rab11. We describe a related protein, arfophilin-2, that interacts with Arf5 in a nucleotide-dependent manner, but not Arf1, 4, or 6 and also binds Rab11. Arfophilin-2 localized to a perinuclear compartment, the centrosomal area, and focal adhesions. The localization of arfophilin-2 to the perinuclear compartment was selectively blocked by overexpression of Arf5-T31N. In contrast, a green fluorescent protein-arfophilin-2 chimera or arfophilin-2 deletions were localized around the centrosome in a region that was also enriched for transferrin receptors and Rab11 but not early endosome markers, suggesting that the distribution of the endosomal recycling compartment was altered. The arfophilins belong to a conserved family that includes Drosophila melanogaster nuclear fallout, a centrosomal protein required for cellularization. Expression of green fluorescent protein-nuclear fallout in HeLa cells resulted in a similar phenotype, indicative of functional homology and thus implicating the arfophilins in mitosis/cytokinesis. We suggest that the novel dual GTPase-binding capacity of the arfophilins could serve as an interface of signals from Rab and Arf GTPases to regulate membrane traffic and integrate distinct signals in the late endosomal recycling compartment.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • ADP-Ribosylation Factors / metabolism*
  • Amino Acid Sequence
  • Animals
  • Biological Transport
  • CHO Cells
  • Carrier Proteins / genetics
  • Carrier Proteins / metabolism*
  • Centrosome / metabolism
  • Cloning, Molecular
  • Cricetinae
  • Cricetulus
  • Drosophila Proteins / genetics
  • Drosophila Proteins / metabolism
  • Endosomes / metabolism*
  • HeLa Cells
  • Humans
  • Mitosis / genetics
  • Molecular Sequence Data
  • Nuclear Proteins / genetics
  • Nuclear Proteins / metabolism
  • Protein Binding
  • Sequence Homology
  • Two-Hybrid System Techniques
  • rab GTP-Binding Proteins / metabolism*

Substances

  • Carrier Proteins
  • Drosophila Proteins
  • Nuclear Proteins
  • RAB11FIP3 protein, human
  • arfophilin
  • nuf protein, Drosophila
  • rab11 protein
  • ADP-Ribosylation Factors
  • rab GTP-Binding Proteins