EHD1 and Eps15 Interact with Phosphatidylinositols via Their Eps15 Homology Domains

• Published in: The Journal of biological chemistry Vol. 282; no. 22; pp. 16612 - 16622
• Main Authors: Naslavsky, Naava, Rahajeng, Juliati, Chenavas, Sylvie, Sorgen, Paul L., Caplan, Steve
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.06.2007; American Society for Biochemistry and Molecular Biology
• Subjects: Adaptor Proteins, Signal Transducing; Animals; Binding Sites - physiology; Calcium - chemistry; Calcium - metabolism; Calcium-Binding Proteins - chemistry; Calcium-Binding Proteins - metabolism; Cell Membrane - chemistry; Cell Membrane - metabolism; Endosomes - chemistry; Endosomes - metabolism; Humans; Intracellular Signaling Peptides and Proteins - chemistry; Intracellular Signaling Peptides and Proteins - metabolism; Nuclear Magnetic Resonance, Biomolecular; Phosphatidylinositols - chemistry; Phosphatidylinositols - metabolism; Phosphoproteins - chemistry; Phosphoproteins - metabolism; Protein Binding - physiology; Protein Structure, Tertiary - physiology; Recombinant Proteins - chemistry; Recombinant Proteins - metabolism; Vesicular Transport Proteins - chemistry; Vesicular Transport Proteins - metabolism
• ISSN: 0021-9258; 1083-351X
• DOI: 10.1074/jbc.M609493200

The C-terminal Eps15 homology domain-containing protein, EHD1, regulates the recycling of receptors from the endocytic recycling compartment to the plasma membrane. In cells, EHD1 localizes to tubular and spherical recycling endosomes. To date, the mode by which EHD1 associates with endosomal membranes remains unknown, and it has not been determined whether this interaction is direct or via interacting proteins. Here, we provide evidence demonstrating that EHD1 has the ability to bind directly and preferentially to an array of phospholipids, preferring phosphatidylinositols with a phosphate at position 3. Previous studies have demonstrated that EH domains coordinate calcium binding and interact with proteins containing the tripeptide asparagine-proline-phenylalanine (NPF). Using two-dimensional nuclear magnetic resonance analysis, we now describe a new function for the Eps15 homology (EH) domain of EHD1 and show that it is capable of directly binding phosphatidylinositol moieties. Moreover, we have expanded our studies to include the C-terminal EH domain of EHD4 and the second of the three N-terminal EH domains of Eps15 and demonstrated that phosphatidylinositol binding may be a more general property shared by certain other EH domains. Further studies identified a positively charged lysine residue (Lys-483) localized within the third helix of the EH domain, on the opposite face of the NPF-binding pocket, as being critical for the interaction with the phosphatidylinositols.