Fig. 2. Schematic models of wt LDLR, wt LpR, LpR_1-790LDLR_791-839, LpR_1-342LDLR_293-839, LDLR_1-292LpR_343-850, LDLR_H562N, LDLR_H562Y and LDLR_H190Y; LDLR domains are depicted in grey and LpR domains in black. LpR_1-790LDLR_791-839 is composed of the ectodomain and transmembrane domain of LpR, and the intracellular tail of LDLR. LpR_1-342LDLR_293-839 harbours the ligand-binding domain of LpR and the region from the EGF domain to the C-terminus of LDLR. LDLR_1-292LpR_343-850 is composed of the ligand-binding domain of LDLR and the region from the EGF domain to the C-terminus of LpR. In the mutant LDLR receptors, His562 is substituted by Tyr (small white circle in the ß-propeller) or Asn (small black circle in the ß-propeller), or His190 is mutated to Tyr (small white square in the fifth cysteine-rich repeat). Squares, ligand-binding domain; diamonds, EGF repeats; circle, ß-propeller; oval, O-linked glycosylation domain; short rectangle, transmembrane domain; long rectangle, intracellular tail.