title: Rab11-FIP3 localises to a Rab11-positive pericentrosomal compartment during interphase and to the cleavage furrow during cytokinesis.
abstract: The Rab11-family interacting protein 3 (Rab11-FIP3), also known as Arfophilin and Eferin, is a Rab11 and ADP-ribosylation factor (ARF) binding protein of unknown function. Here, we sought to investigate the subcellular localisation and elucidate the function of Rab11-FIP3 in eukaryotic membrane trafficking. Utilising a polyclonal antibody specific for Rab11-FIP3, we have demonstrated by immunofluorescence microscopy that Rab11-FIP3 colocalises with Rab11 in a distinctive pericentrosomal location in A431 cells. Additionally, we found that Rab11-FIP3 localises to punctate vesicular structures dispersed throughout A431 cells. We have demonstrated that both Rab11 and Rab11-FIP3 localise to the cleavage furrow during cytokinesis, and that Rab11-FIP3 localisation is dependent on both microtubule and actin filament integrity. We show that Rab11-FIP3 does not enter brefeldin A (BFA) induced membrane tubules that are positive for the transferrin receptor (TfnR). Furthermore, we show that expression of an amino-terminally truncated mutant of Rab11-FIP3 (Rab11-FIP3((244-756))) does not inhibit transferrin (Tfn) recycling in HeLa cells. It is likely that Rab11-FIP3 is involved in trafficking events other than Tfn trafficking; these may include the transport of endosomally derived membrane to the cleavage furrow during cytokinesis.
authors.affiliation: Molecular Cell Biology Laboratory, Department of Biochemistry, Biosciences Institute, University College Cork, Cork, Ireland.
authors.forename: Conor P
authors.initials: CP
authors.lastname: Horgan
authors.forename: Melanie
authors.initials: M
authors.lastname: Walsh
authors.forename: Tomas H
authors.initials: TH
authors.lastname: Zurawski
authors.forename: Mary W
authors.initials: MW
authors.lastname: McCaffrey
mesh_terms: D020727:ADP-Ribosylation Factors / Q000378:metabolism; D000199:Actins / Q000737:chemistry; D000595:Amino Acid Sequence; D020126:Brefeldin A / Q000494:pharmacology; D002352:Carrier Proteins / Q000737:chemistry*; D002455:Cell Division; D045744:Cell Line, Tumor; D018385:Centrosome / Q000378:metabolism / Q000648:ultrastructure*; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000378:metabolism; D011992:Endosomes / Q000378:metabolism; D006367:HeLa Cells; D006801:Humans; D015151:Immunoblotting; D007399:Interphase; D008856:Microscopy, Fluorescence; D008969:Molecular Sequence Data; D009154:Mutation; D010957:Plasmids / Q000378:metabolism; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D011500:Protein Synthesis Inhibitors / Q000494:pharmacology; D011990:Receptors, Transferrin / Q000737:chemistry; D011994:Recombinant Proteins / Q000737:chemistry; D017386:Sequence Homology, Amino Acid; D014162:Transfection; D014168:Transferrin / Q000737:chemistry; D020691:rab GTP-Binding Proteins / Q000737:chemistry*; D000099193:rab11 GTP-Binding Proteins
chemical_list: D020727:ADP-Ribosylation Factors; D000199:Actins; D020126:Brefeldin A; D002352:Carrier Proteins; D018076:DNA, Complementary; D011500:Protein Synthesis Inhibitors; D011990:Receptors, Transferrin; D011994:Recombinant Proteins; D014168:Transferrin; D020691:rab GTP-Binding Proteins; D000099193:rab11 GTP-Binding Proteins; C439063:RAB11FIP3 protein, human