EHD1 (EH domain containing 1) is an ATP- and membrane-binding protein that plays crucial roles in endocytic trafficking, membrane remodeling, and ciliogenesis. The protein controls membrane reorganization through ATP hydrolysis and is essential for endosomal membrane fusion and recycling endosome trafficking 1. EHD1 regulates basal cell surface expression of EGFR by controlling transport from the Golgi to the plasma membrane, which is functionally important for EGF-induced cell proliferation 1. In endosomal fission processes, EHD1 works downstream of MICAL-L1 and FCHSD2, contributing to ARP2/3-mediated actin branching and receptor recycling 2. Clinically, EHD1 dysfunction has significant disease implications. A homozygous missense mutation (p.R398W) causes an autosomal recessive disorder characterized by sensorineural deafness and tubular proteinuria due to impaired proximal tubular endocytosis 3. This mutation also leads to male infertility in mice through disrupted spermatogenesis, affecting acrosome formation and sperm tail development 4. Additionally, EHD1 promotes cancer progression by facilitating PD-L1 recycling, thereby enabling tumor immune evasion in lung adenocarcinoma 5, and enhances breast cancer metastasis through mTOR-HIF2α pathway activation 6. These findings establish EHD1 as a critical regulator of membrane trafficking with important roles in development, reproduction, and disease.