Role of Phosphatidylinositol 4,5-Bisphosphate in Regulating EHD2 Plasma Membrane Localization
Figure 9
Model of EHD2 and EHD1 membrane localization.
EHD2 localizes to the plasma membrane, and is predicted to form large oligomers at the neck of caveolae. PIP2, which is enriched in plasma membrane domains, including caveolae, has a crucial role in maintaining EHD2 at the cell surface. In the absence of caveolar invaginations, EHD2 maintains its plasma membrane association, likely through binding to PIP2 and, potentially, protein interactions mediated outside of the EH2 domain. EHD2 binds to the F-BAR domain-containing protein syndapin2, which facilitates membrane curvature, and also to EHBP1, which connects to the actin cytoskeleton. In contrast, localization of EHD1 to tubular recycling endosomes depends on binding of the EH1 domain to MICAL-L1 and sydnapin2, which require phosphatidic acid for their recruitment to the tubular recycling endosomes.