Phosphatidic acid induces EHD3-containing membrane tubulation and is required for receptor recycling

EHD3 is localized on the tubular structures of early endosomes, and it regulates their trafficking pathway. However, the regulatory mechanism of EHD3-containing tubular structures remains poorly understood. An in vitro liposome co-sedimentation assay revealed that EHD3 interacted with phosphatidic acid through its helical domain and this interaction induced liposomal tubulations. Additionally, inhibiting phosphatidic acid synthesis with diacylglycerol kinase inhibitor or lysophosphatidic acid acyltransferase inhibitor significantly reduced the number of EHD3-containing tubules and impaired their trafficking from early endosomes. These results suggest that EHD3 and phosphatidic acid cooperatively regulate membrane deformation and trafficking from early endosomes.