Low Density Lipoprotein Receptor (LDLR)

The Low-Density Lipoprotein (LDL) Receptor is a mosaic protein that mediates the endocytosis of cholesterol-rich LDL. It is a cell-surface receptor that recognizes the apoprotein B100 which is embedded in the phospholipid outer layer of LDL particles. The receptor also recognizes the apoE protein found in chylomicron remnants and VLDL remnants (IDL). Brown and Goldstein won a Nobel Prize for their identification of the Low Density Lipoprotein (LDL) receptor in 1985 whilst they were studying familial hypercholesterolemia.

The LDL receptor can be described as a chimeric protein. It is made up of a number of functionally distinct domains that can function independently of each other.