TY - JOUR
T1 - Membrane localization is critical for activation of the PICK1 BAR domain
AU - Madsen, Kenneth L
AU - Eriksen, Jacob
AU - Milan-Lobo, Laura
AU - Han, Daniel S
AU - Niv, Masha Y
AU - Ammendrup-Johnsen, Ina
AU - Henriksen, Ulla
AU - Bhatia, Vikram K
AU - Stamou, Dimitrios
AU - Sitte, Harald H
AU - McMahon, Harvey T
AU - Weinstein, Harel
AU - Gether, Ulrik
N1 - Keywords: Animals; Biological Transport; COS Cells; Carrier Proteins; Cell Membrane; Cercopithecus aethiops; Gene Expression Regulation; Hippocampus; Ligands; Lipids; Models, Biological; Nuclear Proteins; Protein Conformation; Protein Structure, Secondary; Protein Structure, Tertiary; Rats
PY - 2008
Y1 - 2008
N2 - The PSD-95/Discs-large/ZO-1 homology (PDZ) domain protein, protein interacting with C kinase 1 (PICK1) contains a C-terminal Bin/amphiphysin/Rvs (BAR) domain mediating recognition of curved membranes; however, the molecular mechanisms controlling the activity of this domain are poorly understood. In agreement with negative regulation of the BAR domain by the N-terminal PDZ domain, PICK1 distributed evenly in the cytoplasm, whereas truncation of the PDZ domain caused BAR domain-dependent redistribution to clusters colocalizing with markers of recycling endosomal compartments. A similar clustering was observed both upon truncation of a short putative alpha-helical segment in the linker between the PDZ and the BAR domains and upon coexpression of PICK1 with a transmembrane PDZ ligand, including the alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor GluR2 subunit, the GluR2 C-terminus transferred to the single transmembrane protein Tac or the dopamine transporter C-terminus transferred to Tac. In contrast, transfer of the GluR2 C-terminus to cyan fluorescent protein, a cytosolic protein, did not elicit BAR domain-dependent clustering. Instead, localizing PICK1 to the membrane by introducing an N-terminal myristoylation site produced BAR domain-dependent, but ligand-independent, PICK1 clustering. The data support that in the absence of PDZ ligand, the PICK1 BAR domain is inhibited through a PDZ domain-dependent and linker-dependent mechanism. Moreover, they suggest that unmasking of the BAR domain's membrane-binding capacity is not a consequence of ligand binding to the PDZ domain per se but results from, and coincides with, recruitment of PICK1 to a membrane compartment.
AB - The PSD-95/Discs-large/ZO-1 homology (PDZ) domain protein, protein interacting with C kinase 1 (PICK1) contains a C-terminal Bin/amphiphysin/Rvs (BAR) domain mediating recognition of curved membranes; however, the molecular mechanisms controlling the activity of this domain are poorly understood. In agreement with negative regulation of the BAR domain by the N-terminal PDZ domain, PICK1 distributed evenly in the cytoplasm, whereas truncation of the PDZ domain caused BAR domain-dependent redistribution to clusters colocalizing with markers of recycling endosomal compartments. A similar clustering was observed both upon truncation of a short putative alpha-helical segment in the linker between the PDZ and the BAR domains and upon coexpression of PICK1 with a transmembrane PDZ ligand, including the alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor GluR2 subunit, the GluR2 C-terminus transferred to the single transmembrane protein Tac or the dopamine transporter C-terminus transferred to Tac. In contrast, transfer of the GluR2 C-terminus to cyan fluorescent protein, a cytosolic protein, did not elicit BAR domain-dependent clustering. Instead, localizing PICK1 to the membrane by introducing an N-terminal myristoylation site produced BAR domain-dependent, but ligand-independent, PICK1 clustering. The data support that in the absence of PDZ ligand, the PICK1 BAR domain is inhibited through a PDZ domain-dependent and linker-dependent mechanism. Moreover, they suggest that unmasking of the BAR domain's membrane-binding capacity is not a consequence of ligand binding to the PDZ domain per se but results from, and coincides with, recruitment of PICK1 to a membrane compartment.
U2 - 10.1111/j.1600-0854.2008.00761.x
DO - 10.1111/j.1600-0854.2008.00761.x
M3 - Journal article
C2 - 18466293
SN - 1398-9219
VL - 9
SP - 1327
EP - 1343
JO - Traffic - International Journal of Intracellular Transport
JF - Traffic - International Journal of Intracellular Transport
IS - 8
ER -