TY - JOUR
T1 - Flotillin-1/reggie-2 traffics to surface raft domains via a novel Golgi-independent pathway. Identification of a novel membrane targeting domain and a role for palmitoylation
AU - Morrow, Isabel C.
AU - Rea, Shane
AU - Martin, Sally
AU - Prior, Ian A.
AU - Prohaska, Rainer
AU - Hancock, John F.
AU - James, David E.
AU - Parton, Robert G.
PY - 2002/12/13
Y1 - 2002/12/13
N2 - Flotillins are lipid raft-associated proteins, which have been implicated in neuronal regeneration and insulin signaling. We now show that newly synthesized flotillin-1 reaches the plasma membrane via a Sar1-independent and hrefeldin A-resistant targeting pathway. Consistent with post-translational membrane association of flotillin, protease sensitivity experiments suggest that flotillin-1 is not a transmemhrane protein but is associated with the cytoplasmic face of the plasma membrane. The N terminus of flotillin contains a prohibitin-like domain (PHB), which shows homology to a number of proteins associated with raft domains including stomatin, podocin, and prohibitin. We show that the PHB domain of flotillin can efficiently target a heterologous protein, green fluorescent protein, to the plasma membrane. Another PHB-containing protein, stomatin, traffics to the plasma membrane via the conventional secretory pathway. Plasma membrane association of both full-length flotillin and the green fluorescent protein-tagged PHB domain of flotillin is dependent on palmitoylation and requires a conserved cysteine residue, Cys-34, in the PHB domain. The results identify a novel targeting mechanism for plasma membrane association of flotillin-1 involving a Golgi-independent trafficking pathway, the PHB domain, and palmitoylation.
AB - Flotillins are lipid raft-associated proteins, which have been implicated in neuronal regeneration and insulin signaling. We now show that newly synthesized flotillin-1 reaches the plasma membrane via a Sar1-independent and hrefeldin A-resistant targeting pathway. Consistent with post-translational membrane association of flotillin, protease sensitivity experiments suggest that flotillin-1 is not a transmemhrane protein but is associated with the cytoplasmic face of the plasma membrane. The N terminus of flotillin contains a prohibitin-like domain (PHB), which shows homology to a number of proteins associated with raft domains including stomatin, podocin, and prohibitin. We show that the PHB domain of flotillin can efficiently target a heterologous protein, green fluorescent protein, to the plasma membrane. Another PHB-containing protein, stomatin, traffics to the plasma membrane via the conventional secretory pathway. Plasma membrane association of both full-length flotillin and the green fluorescent protein-tagged PHB domain of flotillin is dependent on palmitoylation and requires a conserved cysteine residue, Cys-34, in the PHB domain. The results identify a novel targeting mechanism for plasma membrane association of flotillin-1 involving a Golgi-independent trafficking pathway, the PHB domain, and palmitoylation.
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U2 - 10.1074/jbc.M209082200
DO - 10.1074/jbc.M209082200
M3 - Article
C2 - 12370178
AN - SCOPUS:0037073697
VL - 277
SP - 48834
EP - 48841
JO - Journal of Biological Chemistry
JF - Journal of Biological Chemistry
SN - 0021-9258
IS - 50
ER -