Abstract
FENS-1 and DFCP1 are recently discovered proteins containing one or two FYVE-domains respectively. We show that the FYVE domains in these proteins can bind PtdIns3P in vitro with high specificity over other phosphoinositides. Exogenously expressed FENS-1 localises to early endosomes: this localisation requires an intact FYVE domain and is sensitive to wortmannin inhibition. The isolated FYVE domain of FENS-1 also localises to endosomes. These results are consistent with current models of FYVE-domain function in this cellular compartment. By contrast, exogenously expressed DFCP1 displays a predominantly Golgi, endoplasmic reticulum (ER) and vesicular distribution with little or no overlap with FENS-1 or other endosomal markers. Overexpression of DFCP1 was found to cause dispersal of the Golgi compartment defined by giantin and gpp130-staining. Disruption of the FYVE domains of DFCP1 causes a shift to more condensed and compact Golgi structures and overexpression of this mutant was found to confer significant protection to the Golgi against brefeldin-induced dispersal. These properties of DFCP1 are surprising, and suggest FYVE domain-localisation and function may not be exclusively endosomal. Movies available on-line
Publication types
-
Research Support, Non-U.S. Gov't
MeSH terms
-
Androstadienes / pharmacology
-
Animals
-
Brefeldin A / pharmacology
-
COS Cells
-
Carrier Proteins / chemistry
-
Carrier Proteins / genetics
-
Carrier Proteins / metabolism*
-
Endosomes / chemistry
-
Endosomes / drug effects
-
Endosomes / metabolism*
-
Enzyme Inhibitors / pharmacology
-
Golgi Apparatus / drug effects
-
Golgi Apparatus / metabolism*
-
Golgi Matrix Proteins
-
Green Fluorescent Proteins
-
Humans
-
Indicators and Reagents / metabolism
-
Luminescent Proteins / genetics
-
Luminescent Proteins / metabolism
-
Membrane Lipids / metabolism
-
Membrane Proteins / metabolism
-
Phosphatidylinositol Phosphates / metabolism*
-
Protein Binding
-
Protein Structure, Tertiary
-
Protein Synthesis Inhibitors / pharmacology
-
Protein Transport
-
Proteins / chemistry
-
Proteins / genetics
-
Proteins / metabolism*
-
Recombinant Fusion Proteins / genetics
-
Recombinant Fusion Proteins / metabolism
-
Surface Plasmon Resonance
-
Wortmannin
-
Zinc Fingers
Substances
-
Androstadienes
-
Carrier Proteins
-
Enzyme Inhibitors
-
Golgi Matrix Proteins
-
Indicators and Reagents
-
Luminescent Proteins
-
Membrane Lipids
-
Membrane Proteins
-
Phosphatidylinositol Phosphates
-
Protein Synthesis Inhibitors
-
Proteins
-
Recombinant Fusion Proteins
-
ZFYVE1 protein, human
-
macrogolgin
-
phosphatidylinositol 3-phosphate
-
Green Fluorescent Proteins
-
Brefeldin A
-
Wortmannin