PCTP (phosphatidylcholine transfer protein) is a cytosolic protein that catalyzes the intermembrane transfer of phosphatidylcholine molecules between cellular membranes 1. The protein binds a single phosphatidylcholine molecule and facilitates its transport across membrane compartments, with its structure comprising a hydrophobic pocket and well-defined head group binding site 2. PCTP plays critical roles in platelet activation by enhancing dense granule secretion and contributing to PAR4-mediated platelet responses, with higher expression levels associated with increased platelet reactivity 34. The protein also regulates metabolic processes by limiting fatty acid access to mitochondria through stimulation of thioesterase superfamily member 2 (Them2), influencing hepatic lipid metabolism and insulin sensitivity 25. PCTP expression is transcriptionally regulated by RUNX1 and exhibits racial differences, with higher expression in platelets from black subjects compared to white subjects 67. Clinically, elevated PCTP expression is associated with increased risk of death and myocardial infarction in cardiovascular disease patients, highlighting its potential as a biomarker and therapeutic target 6. The human PCTP gene is located on chromosome 17-22 1.