Low-Density Lipoprotein Receptor (LDLR) is a transmembrane glycoprotein that plays a critical role in cholesterol homeostasis. LDLR mediates blood cholesterol level by interacting with lipoprotein particles like LDL and VLDL. The extracellular domain of LDLR contains LDL receptor type A (ligand-binding) modules (LA repeats), epidermal growth factor-like modules, and LY repeats containing the YWTD consensus motif that are important in binding and releasing of ApoB-100 and ApoE in lipoprotein particles. The C terminal domain of LDLR inside the cell is required for the receptor internalization. Loss of function mutations in the LDLR gene causes Familial Hypercholesterolemia (FH).