Reactome | LRP1 (CD91) binds Hemopexin:heme

LRP1 (CD91) binds Hemopexin:heme

Stable Identifier

R-HSA-2168897

Type

Reaction [binding]

Species

Homo sapiens

Compartment

extracellular region, plasma membrane

ReviewStatus

5/5

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Once formed in the plasma, the hemopexin:heme complex is rapidly cleared from circulation and it is taken up by the liver (Smith and Morgan 1984, Smith and Morgan 1985, Tolosano et al. 2010, Vinchi et al. 2008), where heme is degraded by heme oxygenases. In mouse, rat and rabbit several experimental evidences led to the postulation of a specific receptor on hepatocytes with high affinity for the hemopexin:heme complex (Smith and Morgan 1981, Smith and Morgan 1984, Smith et al, 1988, Smith et al., 1991), but such a receptor has not been identified to date. The only known hemopexin:heme receptor is LRP1 (CD91) that is ubiquitously expressed and has a low affinity for the complex. LRP1 is a multi-ligand scavenger receptor, involved in endocytosis in some cells types, for example macrophages, and in signaling in other cell types (reviewed in Boucher and Herz 2011). LRP1 is known to act in the metabolism of lipoprotein and it is expressed in several cell types including macrophages, hepatocytes and neurons. Among several ligands, LRP1 (CD91) can bind the hemopexin:heme complex (Hvidberg et al. 2005).

Literature References

PubMed ID	Title	Journal	Year
6480598	Hemopexin-mediated heme uptake by liver. Characterization of the interaction of heme-hemopexin with isolated rabbit liver plasma membranes Smith, A, Morgan, WT	J. Biol. Chem.	1984
1646599	The murine haemopexin receptor. Evidence that the haemopexin-binding site resides on a 20 kDa subunit and that receptor recycling is regulated by protein kinase C Farooqui, SM, Smith, A, Morgan, WT	Biochem. J.	1991
15947085	Identification of the receptor scavenging hemopexin-heme complexes Møller, HJ, Højrup, P, Hvidberg, V, Moestrup, SK, Maniecki, MB, Jacobsen, C	Blood	2005
3891754	Hemopexin-mediated heme transport to the liver. Evidence for a heme-binding protein in liver plasma membranes Smith, A, Morgan, WT	J. Biol. Chem.	1985
19650691	Heme scavenging and the other facets of hemopexin Fagoonee, S, Fiorito, V, Tolosano, E, Vinchi, F, Morello, N	Antioxid. Redox Signal.	2010
18556779	Hemopexin prevents endothelial damage and liver congestion in a mouse model of heme overload Gastaldi, S, Altruda, F, Tolosano, E, Silengo, L, Vinchi, F	Am. J. Pathol.	2008
20920479	Signaling through LRP1: Protection from atherosclerosis and beyond Boucher, P, Herz, J	Biochem. Pharmacol.	2011
2833500	Importance of ligand-induced conformational changes in hemopexin for receptor-mediated heme transport Muster, P, Smith, A, Morgan, WT, Burch, MK, Tatum, FM	J. Biol. Chem.	1988
7287740	Hemopexin-mediated transport of heme into isolated rat hepatocytes Smith, A, Morgan, WT	J. Biol. Chem.	1981