PITPNM2 is a membrane-associated phosphatidylinositol transfer protein that catalyzes the non-vesicular transport of phosphatidylinositol (PI) and phosphatidylcholine between intracellular membranes and the plasma membrane 1. As a multi-domain protein with an N-terminal PITP domain and calcium-binding capability 1, PITPNM2 functions by extracting PI molecules and depositing them at specific membrane compartments, particularly at endoplasmic reticulum-plasma membrane contact sites to support phosphoinositide synthesis 1. PITPNM2 plays a critical role in T cell receptor (TCR) signaling by promoting phosphatidylinositol 4,5-bisphosphate (PIP2) replenishment following TCR stimulation, essential for calcium mobilization and thymocyte development 2. The gene is located on chromosome 12 3 and shares evolutionary conservation with Drosophila rdgB, with rdgB knockdown reducing nocturnal sleep in fruit flies, suggesting conserved sleep-regulatory functions 4. Dysregulated PITPNM2 expression associates with multiple diseases: it is identified as a biomarker in glioblastoma progression where lower expression correlates with disease advancement 5, shows altered expression in breast cancer with associations to poor overall survival 6, and rare variants are implicated in bipolar disorder 7. These findings position PITPNM2 as a key regulator of lipid dynamics with implications for immune signaling and neurological disease.