Rab14 is part of the early endosomal clathrin-coated TGN microdomain.
Rab14 localizes to the Golgi/TGN and to early endosomes, but its biological function remains unclear. By structural modeling, we identified Rab14-specific residues and established a close relationship between the Rab2/Rab4/Rab14, Rab11/25 and Rab39 sub-groups within the Rab protein family. By quantitative confocal microscopy and by density centrifugation we show that Rab14 is part of the early endosomal AP-1 microdomain. Overexpression of a dominant-negative Rab14 GTP-binding mutant that solely localizes to the Golgi donor compartment accelerated EGF degradation. We suggest that the AP-1 microdomain represents the interconnecting compartment in which Rab14 vesicles cycle between early endosomes and the Golgi cisternae.
Proikas-Cezanne
Tassula
T
Autophagy Laboratory, Department of Molecular Biology, Institute for Cell Biology, University of Tuebingen, Auf der Morgenstelle 15, 72076 Tuebingen, Germany. tassula.proikas-cezanne@uni-tuebingen.de
Gaugel
Anja
A
Frickey
Tancred
T
Nordheim
Alfred
A
D002966:Clathrin / Q000235:genetics / Q000378:metabolism; D022163:Clathrin-Coated Vesicles / Q000235:genetics / Q000378:metabolism*; D011992:Endosomes / Q000235:genetics / Q000378:metabolism*; D015870:Gene Expression; D005799:Genes, Dominant; D006367:HeLa Cells; D006801:Humans; D021962:Membrane Microdomains / Q000235:genetics / Q000378:metabolism*; D018613:Microscopy, Confocal / Q000379:methods; D009154:Mutation; D017434:Protein Structure, Tertiary / Q000235:genetics; D021381:Protein Transport / Q000235:genetics; D020691:rab GTP-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D021601:trans-Golgi Network / Q000235:genetics / Q000378:metabolism*
D002966:Clathrin; D020691:rab GTP-Binding Proteins