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Cholesterol transport proteins are proteins that bind, recognize, translocate, exchange, import, export, or distribute cholesterol among extracellular lipoprotein particles, cellular membranes, and intracellular organelles. They coordinate cholesterol flux through receptor-mediated uptake of lipoprotein-derived cholesterol, transmembrane transport across cellular or organellar membranes, efflux to extracellular acceptors, and non-vesicular transfer at membrane contact sites ^[1][2][3]. This functional group includes lipoprotein receptors and apolipoprotein-associated components, ATP-binding cassette transporters, Niemann–Pick C proteins, and soluble lipid-transfer proteins containing sterol-binding domains ^[4]. Their activities depend on cholesterol-binding sites, membrane association, protein–protein interactions, concentration gradients, and, for active transporters, energy coupling. Together, cholesterol transport proteins maintain the heterogeneous distribution of unesterified cholesterol required across the plasma membrane, endosomes, lysosomes, endoplasmic reticulum, mitochondria, and other cellular compartments ^[2][3][4].