PITPNM1 (phosphatidylinositol transfer protein membrane associated 1) is a lipid transfer protein that catalyzes phosphatidylinositol (PI) transfer between membranes with binding affinity for PI > phosphatidic acid > phosphatidylcholine 1. As a multi-domain PITP family member 2, PITPNM1 functions as a PI/PA exchanger at endoplasmic reticulum-plasma membrane contact sites, maintaining phosphoinositide signaling 3. The protein regulates RHOA activity and cytoskeleton remodeling 4, is necessary for cytokinesis completion 5, and maintains Golgi apparatus structure and diacylglycerol levels 67. PITPNM1 supports protein export from the ER-Golgi 6 and binds calcium ions 8. Clinically, PITPNM1 shows disease relevance across multiple conditions. In osteoarthritis, the miR-490-5p/PITPNM1/PI3K/AKT axis regulates chondrogenic differentiation and chondrocyte homeostasis 9. PITPNM1 is essential for endothelial angiogenesis, with knockdown reducing cell viability, proliferation, migration, and VEGF-mediated AKT/ERK signaling 3. In breast cancer, elevated PITPNM1 expression predicts poor prognosis 10, enhances epithelial-mesenchymal transition, and promotes metastasis through PI3K/AKT and ERK1/2 pathways 11. PITPNM1 variants are associated with telomere length 12 and represent candidates for disease discovery 13.