Characterization of a naturally occurring degradation product of the LDL receptor

► The cell-surface LDLR is cleaved between ligand-binding repeats 4 and 5. ► The cleavage enzyme is secreted from the cells. ► The truncated LDLR is unable to bind LDL. ► The half-life of the truncated LDLR is similar to that of the full-length LDLR. ► The truncated LDLR constitute approximately 1/3 of the cell-surface LDLR.