ABCMdb

ABCG2 p.Ser248Phe

Predicted by SNAP2:	A: D (80%), C: D (91%), D: D (91%), E: D (91%), F: D (91%), G: D (91%), H: D (91%), I: D (95%), K: D (91%), L: D (95%), M: D (85%), N: D (85%), P: D (95%), Q: D (91%), R: D (91%), T: D (91%), V: D (91%), W: D (95%), Y: D (95%),
Predicted by PROVEAN:	A: D, C: D, D: D, E: D, F: D, G: D, H: D, I: D, K: D, L: D, M: D, N: D, P: D, Q: D, R: D, T: D, V: D, W: D, Y: D,

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Publications
[hide] Determinants of the activity and substrate recogni... Drug Metab Rev. 2014 Nov;46(4):459-74. doi: 10.3109/03602532.2014.942037. Epub 2014 Jul 18. Szafraniec MJ, Szczygiel M, Urbanska K, Fiedor L
Determinants of the activity and substrate recognition of breast cancer resistance protein (ABCG2).
Drug Metab Rev. 2014 Nov;46(4):459-74. doi: 10.3109/03602532.2014.942037. Epub 2014 Jul 18., [PMID:25036722]

Abstract [show]
The xenobiotic transporters are among the most important constituents of detoxification system in living organisms. Breast cancer resistance protein (BCRP/ABCG2) is one of the major transporters involved in the efflux of xenobiotics. To understand its role in chemotherapeutic and multidrug resistance, it is crucial to establish the determinants of its substrate specificity, which obviously is of high relevance for successful therapy of many diseases. This article summarizes the current knowledge about the substrate preferences of BCRP. We overview the factors which determine its activity, inhibition and substrate recognition, focusing on the structural features of the transporter. BCRP substrate specificity is quite low as it interacts with a spectrum of substances with only a few common features: hydrophobic and aromatic regions, possibly a flat conformation and the metal ion-, oxygen- and nitrogen-containing functionalities, most of which may be the donors/acceptors of H-bonds. Several amino acid residues and structural motifs are responsible for BCRP activity and substrate recognition. Thus, the active form of BCRP, at least a dimer or a larger oligomer is maintained by intramolecular disulfide bridge that involves Cys(603) residues. The GXXXG motif in transmembrane helix 1, Cys residues, Arg(482) and Lys(86) are responsible for maintaining the protein structure, which confers transport activity, and the His(457) or Arg(456) residues are directly involved in substrate binding. Arg(482) does not directly bind substrates, but electrostatically interacts with charged molecules, which initiates the conformational changes that transmit the signal from the transmembrane regions to the ABC domain.

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No. Sentence Comment
203 A model study on plasma membrane vesicles showed that mutations the Glu126 stop, Phe208 Ser, Ser248 Phe, Glu334 stop and Ser441 Asn lead to an inability to transport hematoporphyrin. Login to comment
206 Moreover, Flp-In-293 cells expressing the variants Phe208 Ser, Ser248 Phe, Ser441 Asn and Phe489 Leu were light sensitive when treated with Pheide. Login to comment
209 Position Type of mutation Effect on the transporter References NBD Lys 86 Met (i) No stimulation of the ATPase activity by prazosin; (ii) no influence on the transport of mitoxantrone Henriksen et al. (2005b) Glu 126 stop, Phe 208 Ser, Ser 248 Phe, Glu 334 stop Inability to transport hematoporphyrin Tamura et al. (2006) Glu 211 Gln Complete abolishment of the ATPase activity and methotrexate transport Hou et al. (2009) Pro 392 Ala Significant reduction in the efflux activity of mitoxantrone, BODIPY-prazosin and Hoechst 33342 Ni et al. (2011) TM1 Gly 406 Ala Gly 410 Ala No influence on the activity of the transporter Polgar et al. (2004) Gly 406 Leu Gly 410 Leu (i) Loss of the ability to transport rhodamine123; (ii) impaired transport of mitoxantrone, Pheide and BODIPY-prazosin Polgar et al. (2004) Extracellular loop 1 Phe 431 Leu (i) Loss of the ability to transport methotrexate; (ii) 10% level of hematoporphyrin transport compared to the WT protein Tamura et al. (2006) Ser 441 Asn Inability to transport hematoporphyrin Tamura et al. (2006) Ser 441 Asn Loss of the ability to transport methotrexate Tamura et al. (2006) TM2 Lys 452 Ala His 457 Ala Increase in transport of mitoxantrone, BODIPY-prazosin and Hoechst 33342 Cai et al. (2010) Lys 453 Ala Arg 465 Ala Decrease in transport of mitoxantrone, BODIPY-prazosin, Hoechst 33342, doxorubicin, SN-38 and rhodamine 123 Cai et al. (2010) TM3 Arg 482 Gly Arg 482 Thr (i) No change in the inhibitory activity of lapatinib; (ii) about two times greater inhibition by ritonavir, saquinavir and nalfinavir than in the WT variant; (iii) gaining the ability to transport rhodamine123 and doxorubicin; (iv) no influence on the transport of mitoxantrone; (v) loss of the ability to transport methotrexate Dai et al. (2008), Gupta et al. (2004), Honjo et al. (2001), Mitomo et al. (2003) Arg 482 Thr (i) Lower IC 50 of cyclosporine A for mutant than for WT variant; (ii) lower elacridar inhibition potency Xia et al. (2007) Arg 482 Lys Complete loss of transport activity Ejendal et al. (2006) Phe 489 Leu Impaired transport of porphyrins, no transport of methotrexate Tamura et al. (2006) Extracellular loop 3 Asn 590 Tyr Over twice reduced transport of mitoxantrone, topotecan, daunorubicin and rhodamine 123 Vethanayagam et al. (2005) Cys 592 Ala/Cys 608 Ala (i) Transport of mitoxantrone almost unchanged; (ii) transport of BODIPY-prazosin significantly impaired Henriksen et al. (2005a) Extracellular loop 3 Cys 603 Ser Cys 592 Ser/Cys 608 Ser Cys 592 Ser/Cys 603 Ser/Cys 608 Ser Diminished susceptibility to the inhibitory activity of fumitremorgin C Shigeta et al. (2010) Cys-less Arg 482 Gly-BCRP Complete loss of the ability to efflux mitoxantrone Liu et al. (2008b) The positions of the amino acid residues refer to the topological model of BCRP proposed by Wang et al. (2009). Login to comment