ABCG2 tetramer transports heme from cytosol to extracellular region

Stable Identifier
Reaction [transition]
Homo sapiens
Export of heme to the blood by ABCG2
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Heme is utilised as a prosthetic group in the production of hemoproteins inside cells. However, when intracellular heme accumulation occurs, heme is able to exert its pro-oxidant and cytotoxic action. The amount of free heme must be tightly controlled to maintain cellular homeostasis and avoid pathological conditions (Chiabrando et al. 2014). The tetrameric efflux pump ATP-binding cassette sub-family G member 2 (ABCG2) (Xu et al. 2004) can relieve cells from toxic heme concentrations even against a concentration gradient. It is expressed in placenta, liver, and small intestine (Krishnamurthy et al. 2004, Doyle & Ross 2003, Zhang et al. 2003).

Literature References
PubMed ID Title Journal Year
15001581 Characterization of oligomeric human half-ABC transporter ATP-binding cassette G2

Liu, Y, Xu, J, Bates, S, Zhang, JT, Yang, Y

J. Biol. Chem. 2004
12958161 The expression and functional characterization of ABCG2 in brain endothelial cells and vessels

Stanimirovic, DB, Zhang, H, Mojsilovic-Petrovic, J, Andrade, MF, Ball, M, Zhang, W

FASEB J 2003
15044468 The stem cell marker Bcrp/ABCG2 enhances hypoxic cell survival through interactions with heme

Zhou, S, Sarkadi, B, Ross, DD, Sorrentino, BP, Nakanishi, T, Bailey-Dell, K, Krishnamurthy, P, Schuetz, JD, Mercer, KE

J Biol Chem 2004
14576842 Multidrug resistance mediated by the breast cancer resistance protein BCRP (ABCG2)

Ross, DD, Doyle, LA

Oncogene 2003
Catalyst Activity

ABC-type heme transporter activity of ABCG2 tetramer [plasma membrane]

Orthologous Events
Cross References
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